Is there any way you can find out which devices were previously logged in to your iCloud account even if they are no longer active? If they were removed directly in macOS’ iCloud app, would there be a way to find that information in syslog? Or does Apple provide that information?
Is it possible to determine the exact date and time (if possible) of creation of an Apple ID?   Is there any official or unofficial way to establish this if you don't have the initial sign up information recorded?
Print file content without the first and last lines I know it existed as sort of a folder in Windows Explorer in at least Windows XP, but I just can't seem to find it in Windows 7...  How can I take a picture with my webcam in Windows 7 without using any 3rd party tools? I have an internet connection that I'd like to be enabled only during the day. With multiple household internet devices, this would need to be something disabled at the level of the router.  I don't believe the router offers this sort of functionality, but I'm reasonably familiar with setting up web servers and the like, and I'm wondering if I can set up some sort of proxy server on the internet that the router must go through and have that proxy only active at certain times of day.  It's a bit vague I know, but is something like this even possible?  If not, are there other solutions to the problem? I can say "I feed someone". Am I forced to say "I give someone a drink", or is there a single word for this (as in "I [verb] someone")?  Unfortunately my thesaurus can't really help me. Are $(\mathbb{R},+)$ and $(\mathbb{C},+)$ isomorphic as additive groups?  I know that there is a bijection between $\mathbb{R}$  and $\mathbb{C}$, and  asks whether they are isomorphic as abelian groups, are they referring to the additive abelian group? If so is there any simple isomorphism I can find? I know nothing about Hamel basis. Thanks. Where do the X-Men get all their money/funding? Charles Xavier's father was a "wealthy nuclear scientist". In the beginning, Charles personally bankrolled the Xavier Institute/X-Men using his family's money.   This included, but was not limited to things like upgrading the mansion to house the training levels, providing a helicopter (the predecessor to the Blackbird jet), providing and replacing uniforms, providing health care for injured students, and rebuilding/repairing the mansion and parts of the Danger Room  repeatedly.  These have all been recurring costs. The mansion has been damaged or outright destroyed a ridiculous number of times. X-Men can't get into a fight without someone's uniform getting damaged.   In one of the more recent stories (I believe it was an early issue of Wolverine &amp; The X-Men), a comment is made about how the X-Men are pretty much bankrupt.  Where has all this money come from over all these years?   Xavier may have had a large war chest to start with, but no other income has ever been mentioned to my knowledge. Student's tuition could account for some of it, but there's no way that's going to fund everything. How many possible Enigma machine settings? I'm trying to calculate the amount of settings the enigma machine has. I have found several sites regarding this topic, but it seems like there are two answers to my question. The first answer is 158,962,555,217,826,360,000 and the second is 107,458,687,327,250,619,360,000. Where the difference is that in the second answer, it has been taken into account that the notched rings on the enigma could be set as well, giving 26 * 26 = 676 more settings than the first answer.   But which answer is the right one, and why? How many possible different Enigma machine settings are there and how can one determine this number? Total combinations from number of unique combination? How can you find count of the total combinations possible if you have the count of unique combinations? Suppose I need to form a sum of $3$ using $\{1,2\}$ Unique combn. $(1+1+1)$, $(1+2)$ hence '$2$' unique but total is '$3$' i.e, $(1+1+1)$, $(1+2)$, $(2+1)$ I know the elements used to make the combination Note: Number of unique combinations (ie. 2 here) is known. How can I find the total number of combination given the unique combinations? Why do polarized sunglasses remove (most) reflections on car windows?  I know that both lenses of polarized sunglasses are polarized in the same direction and I can see that reflections in my own windshield and the windows of other cars appear, disappear, or change depending on how I tilt my head, but why?  Why is the light in those reflections polarized?  edit: And why is most of the light in the various reflections on the interior of my own windshield and various windows/windshields at what seem like a variety of angles all polarized in a sufficiently narrow set of ways as to make polarized sunglasses work? Available space not changing when resizing a partition In my computer I have several partitions. I have one partition with Fedora that had just below 40 GB of space, and which I wanted to make bigger. Therefore, using GParted, I moved 10 GB from another partition to the Fedora partition. Now, according to GParted, I should have just below 50 GB (see sda12):  However, from Fedora itself the available space looks different:  This was the same space that was available before I resized the partition. How do I make that space actually available to Fedora? Approximation algorithms for min vector subset-sum over GF(2) In  vzn asked about the following problem, which I'll call Vector-Subset-Sum.     Given a set of vectors $v_i$ over GF(2) and a target vector $y$, is there a subset of the $v_i$ summing to $y$?   In the answers, comments, and referenced papers I noted   The decision problem is in P. The natural minimization problem (finding the smallest subset) is NP-hard. It's related to the problem of finding sparse codewords in a linear code.   My question is: are there any known polynomial-time approximation algorithms for the minimization problem in (2)? I know very little about coding theory, so there may be some obvious or well-known approximation-preserving reductions to (3) that I have not seen. What’s the rule to decide whether you add -er or whether you add -or when creating an agent noun from a verb?    Sometimes it’s -er:      read > reader hate > hater hit > hitter   But other times it’s -or:    meditate > meditator collect > collector I am looking for an example of a sequence which shows that, $a_{n+1} - a_n \to 0$ as $n \to \infty$ does not imply that sequence $a_n$ converges. I have a feeling that the sequence should be an oscillatory one but I am unable to think of an example. Here $p$ and $q$ are co-prime integers. Is it necessarily an algebraic number? Friend was brainwashed by MLM-/ponzi investment scam. What can I do? Recently a friend of mine invited me to hear about “an interesting chance to simply earn money.” Basically we and other invited people drove to a meeting room where a speaker told us about a growing startup where you could invest money in a field where similar investments had an ROI of apparently 1000 times the investment in 6 years. Afterwards there was coffee and small talk together, during which they also indoctrinated people saying, they should avoid talking to people talking bad about the investment (or saying it is scam) because you can't gain money from them and they just want to destroy your business.  You earn money if you invest money and if you refer friends who invest money up to multiple levels. The more you invest yourself the greater percentage you earn for your referrals.  Since I had already seen other ponzi-/MLM-schemes and I am from the field it is based in, I recognized that there is no real product and it is a ponzi-/MLM-scheme. Later I found its name on the official scam warning list of multiple countries.  From what I understand, my friend has already invested multiple months or years worth of income; and is earning an amount of money through referrals that would mean scamming other people directly or indirectly through referrals for possibly several $100,000's per month to earn an additional bonus. He also wants to use his position as a respected member of multiple local youth groups and other community groups to get their members as referrals or in his words “…to give them the opportunity to also simply earn money.”  I tried to convince him that it is just a ponzi scam with my knowledge in this field but he answered with the indoctrinated speech “You don’t need to know the details if it makes you rich or use it. You also don't know how every detail of a smartphone works?”/“My sponsor already earned $x with this” or “If you don't believe in this, just stop talking about it to me and other people or do you want to ruin me, my business and my investments?.” So basically this means I can either make his investment worthless/let him lose everything (he also quit his job) or let him scam other people and motivate them to scam other people.  At the moment you can only withdraw small amounts of money out of it because the company invented some reason but you will be able to withdraw all of it “soon” (=most likely never).  What is the best way to resolve this situation (best meaning with lowest loss of money for everybody)?  Edit: The founders are known names in Ponzi schemes or convicted for crimes like fraudulent bankruptcy and many of their claims are technically impossible or proven to not exist with very high probability according to sites about ponzi schemes. But of course they say "Every bigger company has their scandals".  You can't trade the bought virtual coins outside the company and the only product you can buy can be bought anywhere else for less than 10% of the price without the logo.  When I met other friends they mentioned that they got invitations for the same meeting. I just stated to them that I already went to one and told them the name of the company (which was not stated on the invitation) and that I will not invest in it because there are official warnings that this is a scam. Ways to eliminate switch in code Convert NSDate to NSString How do I convert, NSDate to NSString so that only the year in @"yyyy" format is output to the string? What are examples where a "naive bootstrap" fails? How to know (in GCC) when given macro/preprocessor symbol gets declared? Suppose I have #define foo in various header files. It may expand to some different things. I would like to know (when compiling a .cc file) when a #define is encountered, to what it will expand, it which file it is and where it got included from.  Is it possible? If not, are there any partial solutions that may help?  Feel free to add comments with clarification requests.  Edit: current answers seem to concentrate on the case when there is one #define and I just want to jump to definition or know what the definition is. That's the simple case and yes, your solutions work. But when I have the same #define in different files, and want to know which one kicks in first, none of these techniques is useful. Okay, I actually used #warning carefully to find the right place. But this requires much work. No Dialect mapping for JDBC type: -9