When I inspected my monitor I found a hole with a lock symbol (pictured below).  What is this? What is the function of this hole?    My monitor is a Samsung Syncmaster SA100.
My friend recently received a new digital drawing tablet (Wacom Intuos Pro). Among other features, there is a hole that resembles a charm hole found on mobile phones:    Other parts of the package (e.g. pen) do not have such holes, so it isn't possible to attach them using a band. What is the purpose of this hole? Is it just for attaching various charms and such?
Is a Schengen visa/transit visa required for a transit flight through two Schengen airports? I am travelling form Delhi (DEL) to San Francisco (SFO), I have to make a connection flight in Vienna that would take me to Frankfurt (FRA). My flight to SFO is from FRA, I have one ticket for entire journey and the flights are operated by Lufthansa or its subsidiaries.  Do I need a transit visa? My flight arrives at Vienna international airport and leaves from the same, and for second leg it arrives at Frankfurt international airport.  I asked this question as an addendum to my  but was advised to make a new post.  I hold Indian passport and valid US visa. Problem 4.3.32 in Linear Algebra, Lay:  Let $V$ and $W$ be vector spaces, let $T:V\to W$ be a linear transformation, and let $\{\mathbf{v}_1, \dots , \mathbf{v}_p \}$ be a subset of $V$. Suppose that $T$ is a one-to-one transformation [...]. Show that if the set of images $\{T(\mathbf{v}_1), \dots ,T(\mathbf{v}_p)\}$ is linearly dependent, then $\{\mathbf{v}_1, \dots , \mathbf{v}_p \}$ is linearly dependent. This fact shows that a one-to-one linear transformation maps a linearly independent set onto a linearly independent set.  All I can think of doing: If $\{T(\mathbf{v}_1), \dots ,T(\mathbf{v}_p)\}$ is linearly dependent, then there exist weights $c_1, \dots, c_p$, not all zero, so that $$c_1 T(\mathbf{v}_1) + \cdots + c_p T(\mathbf{v}_p) = \mathbf{0}$$ Since $T$ is linear: $$c_1 T(\mathbf{v}_1) + \cdots + c_p T(\mathbf{v}_p) = T(c_1\mathbf{v}_1) + \cdots + T(c_p \mathbf{v}_p)=T(c_1 \mathbf{v}_1 +\cdots + c_p \mathbf{v}_p)=\mathbf{0}$$ So the set $\{\mathbf{v}_1, \dots , \mathbf{v}_p \}$ must be linearly dependent. Am I missing something? And why must $T$ be on-to-one for this to be true? An example showing that it is not true if $T$ is not one-to-one would be great! Given an array of n Objects, let's say it is an array of strings, and it has the following values:  foo[0] = "a"; foo[1] = "cc"; foo[2] = "a"; foo[3] = "dd";   What do I have to do to delete/remove all the strings/objects equal to "a" in the array? Why is method overloading and overriding needed in java? Dual monitor setup, why does NVidia 340 Prime only detect one monitor? How do I enable or disable Apport? UK visa requirement: Residence or citizenship? On gov.uk's  it is indicated      Check if you need this visa if you’re visiting from outside the European Economic Area (EEA) or Switzerland"   “Visiting from” makes you understand that the country you regularly live in is relevant, thus you can avoid applying for a visa if you are visiting from Italy (as country of regular residency).  As a matter of fact, if you proceed to make the check, the question to answer is "What passport or travel document do you have?", not really consistent with the indication previously given.  So, what is relevant: the country you live in with regular documents (and where you leave from to visit UK) or the country of origin which issued the passport?  To be practical, a Moldovan who is an Italian resident with regular resident card and Italian ID card (but with the note "not valid for expatriation") can avoid applying for a visa if he wants to spend a week-end in London (thus visiting from inside EEA)? What is the volatile keyword useful for? Why is len(Posts.body) incorrect on answers in data.SE? I was trying to find a longest answer on a site, and ran into a weird discrepancy:  shows that  has a length of 36388 (length in the query is defined as LEN(Posts.Body)) Yet, the post clearly only has ~26000 characters, as measured 2 ways:  Copy/pasting full text of the answer in my text editor gives me 26040 characters (the source of the answer with all the markdown, not the rendered text which is even smaller).  Trying to post a new answer that consists of this answer's text twice gives me an error &quot;Body is limited to 30000 characters; you entered 52258&quot; - meaning that the length is under 26100 (not 100% sure where the difference in counts comes from as far as two methods)   Another example from same query:  shows len(body) of 33738 whereas the text of the answer has only 29000 characters. This clearly isn't showing rendered characters, as the rendered character count is LOWER than actual answer text when editing (e.g. links add characters, as do images). How can this data.SE discrepancy be explained? How to completely disable auto-save and versions in Mac OS X Lion? I hate the automatic saving and versioning in Mac OS X Lion.  Is there a way to completely turn it off?  (This has been asked before , but the answer and the linked article are completely wrong, so I thought I'd try again.) Reading a binary file and using Response.BinaryWrite() Good 1st PDE book for self study What is a good PDE book suitable for self study?   I'm looking for a book that doesn't require much prerequisite knowledge beyond undergraduate-level analysis.  My goal is to understand basic solutions techniques as well as some basic theory. Let $ f: \mathbb {R} \rightarrow {\mathbb {R}} $ be given by   $$ f (x) = \left \{\begin {matrix} \sin ({\frac {1} {x}}), &amp; \text {if} \phantom {a} x \neq 0; \\  c, &amp; \text {if} \phantom {a} x = 0 \end {matrix} \right. $$ where $ c \in [-1,1]$. For what values ​​of $c$ is there an antiderivative of $f$?  I do not know of a theorem of the form "if and only if" that  it tells me when a function $ f $ has no antiderivative.  Anyone have a suggestion? How can you sync Blender configs between multiple machines? I run Blender on several machines, it is a hassle to copy configs around, in order that you don't have to configure everything from scratch every time. Is there a sync functionality that does this? What is the $n$ times iterate of $f(x)=\frac{x}{\sqrt{1+x^2}}$? Challenge room locked though I have full health I thought these opened if you have full health. I actually had full + 2 blue hearts before dropping a bomb on myself before taking the screenshot.   But even here I have full health... right? limit: $u_n=\frac{1+2^2+3^3+...+n^n}{n^n}$. Let $u_n=\dfrac{1+2^2+3^3+...+n^n}{n^n}$. Prove that : $$\lim u_n=1$$ I tried to prove that $u_n&lt; something$ have limit  is 1 ; but I can't How can I find the files that were stored on my flash drive before I installed Ubuntu to it?   Edit: No, I didn't format it, my files are still on the flash drive root. I just need to know how to access them there. Can “whose” refer to an inanimate object? We lit a fire whose fuel was old timber wood.   Is the word whose referring to fire, an inanimate object, correct in this sentence? Or is there a more appropriate word? Windows 10 Asks me to Enter a Password I am using Windows 10 Pro x64 on my personal laptop on which I have a single user account with no password. For some reason however, Windows 10 has started asking me to enter a password whenever I boot up my machine. All I have to do is press the button without entering anything, and I log in, but I would much rather skip this step in favor of an automatic sign-in. Why has this started happening only now? What can I do to stop this behavior?