What value should be used for an LED with current rating of 350mA ~ 1000mA
Resistor in series needed with LED string?
Here's what I am trying to do:  1) User creates record A.  2) Time-based workflow sends an email to the Record A creator based on a date field in the record.  3) The email template has a URL link.  4) The URL links to a Visualforce page that is basically a form with fields to be filled out (this Visualforce page is in a managed package) and a save button that creates a new User record.  5) When the User clicks the URL link in the email, the Visualforce page opens in a new window.  6) I would like to pass the values of the fields in record A to pre-fill the Visualforce page fields.   Here's my link:  &lt;a href="https://cs19.visual.force.com/apex/CloneThisUser?Desktop=true&amp;Id={!Pending_User__c.User_to_CloneId__c}&amp;formGroupInputSmall={!Pending_User__c.First_Name__c}   And here's the code from the relevant section of the Visualforce page:  &lt;div class="form-group form-group-sm"&gt;       &lt;!-- &lt;apex:outputLabel styleClass="col-sm-2 control-label" for="formGroupInputSmall"&gt;First Name&lt;/apex:outputLabel&gt; --&gt;       &lt;div class="col-xm-11 col-sm-12"&gt;           &lt;apex:inputField html-placeholder="First Name" styleClass="form-control FirstNameInput"  value="{!u.FirstName}" id="formGroupInputSmall"/&gt;       &lt;/div&gt;     &lt;/div&gt;   I have only included the first field I would like to pass the parameter to, in order to keep this post simple.   The link passes the User_to_Clone_Id__c just fine but does not fill in the "First Name" field with the value of the First_Name__c .  What am I doing incorrectly? Thanks. Why are the laws of thermodynamics "supreme among the laws of Nature"? Eddington wrote     The law that entropy always increases holds, I think, the supreme position among the laws of Nature. If someone points out to you that your pet theory of the universe is in disagreement with Maxwell's equations — then so much the worse for Maxwell's equations. If it is found to be contradicted by observation — well, these experimentalists do bungle things sometimes. But if your theory is found to be against the second law of thermodynamics I can give you no hope; there is nothing for it but to collapse in deepest humiliation.   and Einstein wrote     [classical thermodynamics] is the only physical theory of universal content which I am convinced will never be overthrown, within the framework of applicability of its basic concepts.   Why did they say that? Is it a very deep insight they had, or is it something one can be convinced of quite easily? Or even, is it trivial? Question:   Prove that a norm is always non-negative.   Assume that the norm is negative.   Define: $f: \mathbb{R}^{n}\rightarrow \mathbb{R}^{-}_{0}$  $v \mapsto \left ( \vec{v} \right )f=\left \| \vec{v} \right \|$  $\left ( \vec{u}+\vec{v} \right )f=\left \| \vec{u}+\vec{v} \right \| \in \mathbb{R}^{-}_{0}$ and  $\left ( \vec{u} \right )f=\left \| \vec{u} \right \|,\left ( \vec{v} \right )f=\left \| \vec{v} \right \|=\left \| \vec{v} \right \| \in \mathbb{R}^{-}_{0}$  At this point I am unable to progress further.  Any help is appreciated. Using "you" and "your" as a representation for yourself and everyone in general Example sentence:     I love when your dog just lets you sit there to pet them. You don’t necessarily know if they are enjoying it, but they love you enough to just sit there with you for a bit.   Is this correct? We assume the words "you" and "your" refer to the speaker of the sentence, and not to the listener, as second-person usually does. But it also refers to dog owners in general. I have always been curious about this. Several wands and other magic items in the DMG cite &quot;spellcaster&quot; as an attunement requirement, specifically &quot;requires attunement by a spellcaster&quot; while others list multiple spellcasting classes (e.g., a Staff of Fire &quot;requires attunement by a druid, sorcerer, warlock, or wizard&quot; p. 201). However, all the DMG states in this regard is:  Some magic items require a creature to form a bond with them before their magical properties can be used. This bond is called attunement, and certain items have a prerequisite for it. If the prerequisite is a class, a creature must be a member of that class to attune to the item.¹ (If the class is a spellcasting class, a monster qualifies if that monster has spell slots and uses that class's spell list. [emphasis and footnote added] (p. 136)  The language of the Mage Slayer feat describes a spellcaster as a creature casting or concentrating on a spell.  You have practiced techniques useful in melee combat against spellcasters [...] When a creature within 5 feet of you casts a spell ... [and] When you damage a creature that is concentrating on a spell ... (PHB, p. 168)  From the above, it does not appear that &quot;spellcaster&quot; would necessarily be considered a class or group of classes, so Are characters that can cast spells, regardless of their class(es), considered spellcasters? Or, put another way, Does &quot;spellcaster&quot; (as an attunement prerequisite) mean any creature who can cast a spell or does it mean all classes with the Spellcasting feature? I can think of five particular cases—innate abilities, two subclasses and two feats: High Elves know one wizard cantrip (0-level spell) of their choice. Drow can cast the dancing lights cantrip, 1st-level spell faerie fire and 2nd-level spell darkness. Forest Gnomes know the minor illusion cantrip, and Tieflings can cast the thaumaturgy cantrip and 2nd-level spells hellish rebuke and darkness. Also, many monsters have innate spellcasting abilities, which would trigger the Mage Slayer feat. Starting at 3rd level, both the Eldritch Knight (Fighter Martial Archetype) and Arcane Trickster (Roguish Archetype) gain the ability to cast wizard spells and gain wizard spell slots (potentially) up to 4th-level spells. PHB, pp. 75 &amp; 98. The latter's 17th-level Spell Thief feature also states &quot;you gain the ability to magically steal the knowledge of how to cast a spell from another spellcaster,&quot; (Ibid.) which strongly implies that (at least) the Arcane Trickster is a spellcaster, although neither subclass is specifically listed as a prerequisite for any magic item in the DMG. Eldritch Knight and Arcane Trickster are also found under Multiclassing, Spell Slots in the PHB:  You determine your available spell slots by adding together all your levels in the bard, cleric, druid, sorcerer, and wizard classes, half your levels (rounded down) in the paladin and ranger classes, and a third of your fighter or rogue levels (rounded down) if you have the Eldritch Knight or the Arcane Trickster feature. (p. 164)  With the Ritual Caster feat, a character chooses a spellcasting class (except paladin or ranger) and gains the ability to cast spells of that class with the ritual tag as rituals. The character immediately gets two 1st-level ritual spells of that class and has the potential to (eventually) learn all of the ritual spells of the chosen class. PHB, p. 169. With the Magic Initiate feat, a character chooses a particular spellcasting class (except paladin or ranger) and immediately learns two cantrips and one 1st-level spell from the class with no further advancement. PHB, p. 168. By definition, it seems all of the above would qualify as spellcasters, but I feel spellcaster typically (or maybe traditionally) refers to bard, cleric, druid, paladin, ranger, sorcerer, warlock and wizard.   I believe an exception would be a 13th level or higher Thief (Roguish Archetype) due to the Use Magic Device feature. PHB, p. 97. I am trying to calculate the sum of this infinite series after having read the series chapter of my textbook: $$\sum_{n=1}^{\infty}\frac{1}{4n^2-1}$$  my steps:   $$\sum_{n=1}^{\infty}\frac{1}{4n^2-1}=\sum_{n=1}^{\infty}\frac{2}{4n^2-1}-\sum_{n=1}^{\infty}\frac{1}{4n^2-1}=..help..=sum$$  I am lacking some important properties, I feel I am coming to the right step and cannot spit that out.. Is there anything like GF(6)? Hubble's law says that the universe is expanding. How come the Milky Way and the Andromeda galaxies are on a collision course? How will they end up colliding with each other? Why does Li+ ion move to cathode in Li-ion battery? Global keyboard capture in C# application I want to capture a keyboard shortcut in my application and trigger a dialog to appear if the user presses a keyboard combo even outside of the app. Similar to Google Desktop Search's Ctrl, Ctrl to bring up the search dialog.  I have tried using some keyboard hook modules out there that basically use Win32 interop to get this effect but each implementation I've tried ties down the keyboard to some extent to where you start getting weird behaviors when the application is doing something intensive. Such as loading a large amount of data, this would cause the keyboard and mouse to lockup.  I'm looking for a lightweight solution that would allow this to be done without tying down the keyboard and mouse. How to install Canon LBP2900b drivers? Please describe direct products in the category Rel. How to enumerate with small roman capitals (not lowercases)? Although I have seen many similar questions, none has been useful.   The question is quite simple: How do I reproduce the highlighted numerals in the image below?    Note that the form of the numerals addressed in questions as  is different from this one.  Thank you in advance! Suppose the following dialogue:  ... &quot;I accept only one notion of land property. Namely, 'I am doing my stuff here, therefore I am here&quot;. &quot;But this means,&quot; he responded, &quot;you can break into any place and stay there, using this rule.&quot; &quot;There is another rule, though. Right to act in its most natural sense, 'I am here, therefore I am doing my stuff here.&quot; &quot;But do not these rules put together become circular reasoning?&quot; &quot;Of course, they do,&quot; I put my head closer to him, &quot;and this is exactly that rare case when circular reasoning is not only sufficient, but is necessary.&quot; &quot;But why is that? Circular reasoning never was a correct argument.&quot; &quot;There are many circular things happening in nature. Life forms, for example, exist only in order to produce new life forms or to prolongate their own lifetime. Is there any reason to say this can't be the case for reason itself? Why must reasoning not be circular?&quot; ...  Can circular reasoning ever be justified? For example, we know all the words in our languages can't be defined using other words without the use of circularity. We know logic can't prove itself without circularity. Are these arguments rational? Are there any other arguments where circular reasoning is still rational? At least two questions (, ) on this site indicate that in more than a few isolated cases at least, letters of recommendation are in fact written by the applicant and only signed off (or perhaps rephrased somewhat) by the recommender, who would actually be responsible for writing the letter.  Is there any evidence about the prevalence of this practice that goes beyond anecdotes? I realize that cross-country (cultural) difference may play a role. Creating square buffer around point feature using ArcGIS for Desktop? I would like to create a square buffer from a point feature but I do not understand the code that goes into it.   Similar questions have been asked on the forums.esri website but that was over 10 years ago, and it did not work when I tried the code.  How do I create a square buffer from a point feature? No sound ALC294 Asus ROG Strix 512 Ubuntu 20.04.01 Atiyah-Macdonald, Exercise 5.4 I was having some trouble with the following exercise from Atiyah-Macdonald.     Let $A$ be a subring of $B$ such that $B$ is integral over $A$. Let $\mathfrak{n}$ be a maximal ideal of $B$ and let $\mathfrak{m}=\mathfrak{n} \cap A$ be the corresponding maximal ideal of $A$. Is $B_{\mathfrak{n}}$ integral over $A_{\mathfrak{m}}$?   The book gives a hint which serves as a counter-example. Consider the subring $k[x^{2}-1]$ of $k[x]$ where $k$ is a field, and let $\mathfrak{n}=(x-1)$. I am trying to show that $1/(x+1)$ could not be integral over $k[x^{2}-1]_{\mathfrak{n}^{c}}$.  I have understood why this situation serves as a counterexample. But I am essentially stuck at trying to draw a contradiction. A hint or any help would be great. Using (or not) the word "to" in a sentence ending with "be able" Which of these is grammatically correct?   As educators, we are always looking for ways to reach all the learners in our classroom as effectively as we are able.   As educators, we are always looking for ways to reach all the learners in our classroom as effectively as we are able to. How to keep font preferences in TexWorks 4 The default font is too small on my screen at the resolution I have it, so I like to reset the font to size 12, but it appears I have to do this everytime I launch the program.  How do I make it remember my preferences?