Can someone explain the node shown in this screen capture?
What kind of node is this?
How does passive perception work Total noob question, but the passive perception is confusing. I don't understand how to calculate it or use it, and I need help. Mass and Newton's Second Law What Scoping Class Will  Use? In reading through the release notes I was excited to discover the introduction of a new  tag. That should help lower the barriers to entry! However, the release notes do not specify what the name of the scoping class should be. And since , we're left guessing.  To be explicit about what I'm trying to understand, take  for example:  &lt;apex:page showHeader="false" standardStylesheets="false" sidebar="false" applyHtmlTag="false" applyBodyTag="false" docType="html-5.0"&gt;     &lt;html xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" lang="en"&gt;         &lt;head&gt;             ...             &lt;apex:stylesheet value="{!URLFOR($Resource.REPLACE_WITH_NAME_OF_SLDS_STATIC_RESOURCE, 'assets/styles/salesforce-lightning-design-system-vf.min.css')}" /&gt;         &lt;/head&gt;         &lt;body&gt;              &lt;!-- REQUIRED SLDS WRAPPER --&gt;             &lt;div class="REPLACE_WITH_NAME_OF_CUSTOM_SCOPING_CLASS"&gt;             ...         &lt;/body&gt;     &lt;/html&gt; &lt;/apex:page&gt;   If I replace the &lt;apex:stylesheet&gt; with &lt;apex:slds&gt;, what should I specify for REPLACE_WITH_NAME_OF_CUSTOM_SCOPING_CLASS? How do I get a Realtek RTL8723BE wireless card to work? Replace non-numeric with empty string Quick add on requirement in our project.  A field in our DB to hold a phone number is set to only allow 10 characters.  So, if I get passed "(913)-444-5555" or anything else, is there a quick way to run a string through some kind of special replace function that I can pass it a set of characters to allow?  Regex? How do you reverse a string in place in C or C++? Show that if $f:X\to Y$ is a continuous function if and only if the graph of $f$ is a closed subset of $X\times Y$ Continuous injective map is strictly monotonic Why do some Unicode text messages crash the iPhone OS? Recently a new "glitch" has surfaced over the Internet over the last few weeks where if an iPhone user is sent:    effective.        Power            لُلُصّبُلُلصّبُررً ॣ ॣh ॣ ॣ  冗   via iMessage it crashes the phone OS temporarily and force restarts the receiving phone.  Why does this work? What is a StackOverflowError, what causes it, and how should I deal with them? Does the fact that matrices $A, B$ are similar imply that $A+cI$ is similar to $B+cI$? Let $A, B$ be similar $n \times n$ matrices over (say) $\mathbb{R}.$  Is it the case that $A+cI$ is similar to $B+cI$?    Here is an argument (which seems too good to be true...)  Since $A, B$ are similar, they have the same Jordan form. So we can write $PAP^{-1}=QBQ^{-1}=J$ for $P, Q$ invertible matrices.   Hence we have $P(A+cI)P^{-1}=PAP^{-1}+cI= J+cI.$ Similarly, we find $Q(B+cI)Q^{-1}=J+cI.$  Hence $A+cI$ and $B+cI$ are both similar to $J+cI$ and hence similar to each other.   Is this correct? I have a function defined as follows: $f(x,y)= \dfrac{x^2-y^2}{\left(x^2+y^2\right)^2}$, if $(x,y)\neq (0, 0)$ and $f(x,y)=0$ if $(x,y)=(0,0)$.  Now, $$\int_0^1\int_0^1 f(x,y)\,\text{d}x~\text{d}y=-\frac{\pi}{4}$$ and $$\int_0^1\int_0^1 f(x,y)\,\text{d}y~\text{d}x=\frac{\pi}{4}.$$   The question I have is this: why does this not contradict Fubini's theorem?    thanks. Find the area of the shaded region in the figure below: Find the area of the shaded region in the figure below:    I am completely stuck on how to start off this question. Please help on some guidance on how to start it off. What prevents investors from buying high yield stocks and selling them as soon as their dividend is paid out? What prevents investors from buying high yield stocks and selling them as soon as their dividend is paid out?   I guess I am confused: If you know the yield and when the dividend will be paid out, why not buy a share an instant before the dividend is paid out and then sell it?  Do you have to have held the share for some amount of time to get the dividend? Is there too much volatility in the instant the dividend is paid out? Can you fly over a Medium enemy creature in a 10ft tall corridor? Windows service stops automatically ASP.NET MVC custom routing for search Here is my scenario.  For the example lets say that I need to return a list of cars based on a search criteria.  I would like to have a single View to display the results since the output will be the same, but I need several ways of getting there.  For instance, I may have a Form with a textbox to search by year.  I may have another separate page that contains a hyperlink for all red, Toyota cars.  How do I handle these multiple scenarios in the same View and Controller.  My dilemma is that the search could contain several options… year, make, model, etc but I don’t know where to put them.  What is the best approach for this?  Should I define the parameters in the routing or go with query strings, etc? I have the following equation, where there is a lot of stuff under the sum symbol:  \begin{equation} d(\vec{x},\vec{y})=   \sum_{Z_{xy}\in\vec{Z}_{xy},\forall x\in\vec{x},\forall y\in\vec{y}}      f(Z_{xy}) \end{equation}   In the resulting document, I find it kind of hard to read. Is there a way to write the equation to make the result more readable, e.g. putting the stuff under the sum symbol on different lines? Parenthesis works in bash shell itself, but not in bash script Guinier regime for form factor Why is it such a good idea to plot the logarithm of the form factor vs $Q^2$ in . It seems arbitrary to me.