I am traveling from Toronto to Ahmedabad via Chicago and Doha and same way back. I am traveling from Toronto to Chicago in Air Canada and in Qatar from Chicago to Doha to Ahmedabad. Same way back. How will the baggage claim, customs and immigration work? While coming back, do I have to get my luggage at Chicago airport, undergo customs, and take all the baggage with me on the train, change terminals, and re-check my luggage at the Air Canada counter, or do I not have to worry about my luggage and it gets automatically transferred?
I am flying from Doha to Philadelphia by Qatar Airway. While in Philadelphia, I need to change flight to US Airway. But I only have 1 hour and a half before my next flight to Birmingham. Do I have enough time to check out and check in my baggage?  1.Kuala Lumpur (KUL)  Tue, 21 Jul 2015 20:50  2.Doha (DOH)  Tue, 21 Jul 2015 23:20  3.Doha (DOH)  Wed, 22 Jul 2015 01:10   Philadelphia (PHL)  Wed, 22 Jul 2015 07:45   5.Philadelphia (PHL)  Wed, 22 Jul 2015 09:40 Terminal F  6.Birmingham (BHM)  Wed, 22 Jul 2015 11:00
We put all of our unit tests in their own projects.  We find that we have to make certain classes public instead of internal just for the unit tests.  Is there anyway to avoid having to do this.  What are the memory implication by making classes public instead of sealed? Connecting multiple grounds As I'm relatively new to the electronics world, I was wondering if you can connect multiple  ground terminals (corresponding to several different voltage outputs) to the same ground. Or do they each need their own?  In my case I have 5 lines, one 12V, one 3.3V, two 5V and one variable from a 12V in using a  voltage regulator that already has its own ground. So I'm guessing that each would need its own ground, but it is never bad to ask. I have two classes, Foo and Bar, that have constructors like this:  class Foo {     Foo()     {       // do some stuff     }      Foo(int arg)     {       // do some other stuff     } }  class Bar : Foo {     Bar() : base()     {       // some third thing     } }   Now I want to introduce a constructor for Bar that takes an int, but I want the stuff that happens in Bar() to run as well as the stuff from Foo(int).  Something like this:  Bar(int arg) : Bar(), base(arg) {   // some fourth thing }   Is there any way to do this in C#?  The best I have so far is putting the work done by Bar() into a function, that also gets called by Bar(int), but this is pretty inelegant. Showing $\sum\limits_{p \in P} \frac{1}{p}$ where $P$ is the set of all primes is divergent These two operators commute...but their eigenvectors aren't all the same. Why? The Hamiltonian   $$H =  \left[ \begin{array}{cccc} a &amp; 0 &amp; 0 &amp; -b \\ 0 &amp; 0 &amp; -b &amp; 0\\ 0 &amp; -b &amp; 0 &amp; 0\\ -b &amp; 0 &amp; 0 &amp; -a \end{array} \right] $$  commutes with the qubit exchange operator  $$ P = \left[ \begin{array}{cccc} 1 &amp; 0 &amp; 0 &amp; 0 \\ 0 &amp; 0 &amp; 1 &amp; 0\\ 0 &amp; 1 &amp; 0 &amp; 0\\ 0 &amp; 0 &amp; 0 &amp; 1 \end{array} \right] $$  So I would expect the two to have the same eigenvectors. The eigenvectors of $P$ are easily seen to be $(1,0,0,0)^T; (0,0,0,1)^T; (0,1,1,0)^T ; (0,1,-1,0)^T$. The latter two are also eigenvectors of $H$, but the first two are not. Why? I thought commuting operators shared the same eigenbasis? What is the trajectory of a photon moving through a vacuum? Since electromagnetic energy is carried by photons and moves in forms of waves, does it mean that a single photon when propagating through space doesn't follow the straight path but instead always moves up and down, up and down like a wave. If so another question arises the speed of propagation of light in vacuum is fixed meaning that it will always take the same amount of time for it to travel from point A to point B, but if a photon always moves up and down it will also mean that it travels longer distance than the distance between A and B and so it ill travel faster than light propagates, is it even possible, could you please clarify these concepts for me? How to stop apt from doing anything I have been wanting to understand how to find the sum of this series.   $$1^p + 2^p + 3^p +{\dots} + n^p$$  I am familiar with Gauss' diagonalised adding trick for the sum of the first $n$ natural numbers.  I can prove the formulas for  $$\begin{align}   \sum_{1}^{n} k^2 &amp;= \frac{n(n+1)(2n+1)}{6}\\  \sum_{1}^{n} k^3 &amp;= \frac{n^2(n+1)^2}{4}\\ \sum_{1}^{n} k^4 &amp;= \frac{n(n+1)(2n+1)(3n^2+3n-1)}{30} \\ \end{align}$$  With mathematical induction. But, beyond that even proofs with mathematical induction are difficult.  I'm interested in learning the theory and the proof behind Faulhaber's formula. What is the knowledge required to understand this proof ? Why are so many forces explainable using inverse squares when space is three dimensional? Remove extra header lines from file, except for the first line I have a file that looks like this toy example.  My actual file has 4 million lines, about 10 of which I need to delete.  ID  Data1  Data2 1    100    100 2    100    200 3    200    100 ID  Data1  Data2 4    100    100 ID  Data1  Data2 5    200    200   I want to delete the lines that look like the header, except for the first line.  Final file:  ID  Data1  Data2 1    100    100 2    100    200 3    200    100 4    100    100 5    200    200   How can I do this? I tried to obtain the size of a directory (containing directories and sub directories) by using the ls command with option l. It seems to work for files (ls -l file name), but if I try to get the size of a directory (for instance, ls -l /home), I get only 4096 bytes, although altogether it is much bigger. Change date and time format from csv file without using date -d I have a .csv file contains   Data1|Data2|10/24/2017 8:10:00 AM   I want to change date and time format of column 3 as following:  From 10/24/2017 8:10:00 AM (12-Hour) to 20171024 08:10:00(24-hour).  Not using -d Application of Complex Numbers I was just wondering how complex numbers can be applied in electrical engineering and why we use complex numbers over regular, real numbers for this application (e.g what capabilities does the complex number have that real numbers do not in electrical engineering)?  I have done some research concerning impedances and understand how they are written in complex form, however I am still confused why complex numbers are necessary in this field over regular numbers. Definite Integral: $\int_0^1\frac{x^{2} -1}{\log x}\,dx$ How to figure out the following integral? I have not been able to solve it from some time. $$\int_0^1\frac{x^{2} -1}{\log x}\,dx$$ Difference between "did + verb" and just "verb+ed" This is something I always get confuse with (native language German). As far as I know "did + verb" is something done and finished in the past. But isn't it the same with "verb + ed"? Probability question of hats PHP calculate age Show that $\prod (1- P(A_n))=0$ iff $\sum P(A_n) = \infty$ With CSS, use "..." for overflowed block of multi-lines $f(x)=x/1$ is not injective?