I mostly say "no problem" when I do something and people thank me. I read somewhere that this is not always correct as it shows like I spent no effort which is not always the case and sometimes it's very the opposite. I was advised I should be saying "always welcome" and "glad to help". But it still not appropriate in some cases (for example, when it's the boss who thanks me I don't think I should be saying that). What could be other possible answers in such situation? The more variants the better because I feel like I am reusing the same sentences over and over.
Is "you are welcome" more polite than "no problem"?  What is the general proper reply to a thank-you?
How do I enable or disable the global application menu? I'm fairly excited for Unity, as it looks like a promising new direction for Ubuntu.  However, I do have a concern - will it be possible to use Unity without the global menu?  I have my window manager set to focus-follows-mouse/sloppy focus, and find the productivity gains to be immense. Sloppy focus is incompatible, however, with global menus, as it is possible for the focus to change while you move from window to menu.  Will Unity support an option to use window menus while still using Unity? ML estimate of exponential distribution (with censored data) In Survival Analysis, you assume the survival time of a r.v. $X_i$ to be exponentially distributed. Considering now that I have $x_1,\dots,x_n$ "outcomes" of i.i.d r.v.'s $X_i$. Only some proportion of these outcomes are in fact "fully realized", i.e. the remaining observations are still "alive".   If I wanted to perform a ML estimate for the rate parameter $\lambda$ of the distribution, how can I utilize the non-realized observations in a coherent/appropriate manner? I believe they still contain useful information for the estimation.   Could someone guide me to literature on this topic? I am sure it exists. I am however having trouble finding good keywords/search terms for the topic. given a polynomial $p(x,y)$ from $\mathbb Z[x,y]$. I want to substitute $x=1$ leaving $y$ as it is. The command Value(p,[1,y]) does not work. Can you give me a hint?  After that it gets a little more complicated. Let  $$p(x,y)=x^6+y^6$$ After substituting $x=1$ we have $p(1,y)=1+y^6$. Given a natural number $j$. I want to find all expressions $y^j$ in $p$ and substitute these $y^j$ by $1$ and the others by $0$. In this case (and for $j=6$) we would get $1+1=2$. If $$p(x,y)=x^4y^2+x^2y^6$$ we should get $0+1=1$. Is there any way to do this?  Thanks for reading! edit: Well, it turns out I used the function Value wrong. The right code for my problem would be Value(p,[x,y],[1,y]). So my first question is solved. How do I create a decimal field in Access with Alter Table? I created a bunch of filters in Gmail for a "master account" that receives forwarded mail from all of my accounts.  The filter list and web of labels/folders has grown to be rather long, and therefore a bit burdensome to manage. I would like to edit / delete / consolidate a lot of these filter rules (and folders) but it seems the only way I can interface with them is through the laundry list at Setting/Filters. It'd be cool there was an option to "View/Edit Filter" on an individual email's page, but I'm not sure if something like that currently exists.  What's the best way to view a filter rule currently being applied to an email (in Gmail)? Can a shell script set environment variables of the calling shell? Does the VBA "And" operator evaluate the second argument when the first is false? Difference in number of communities on main site A group $G$ with $G'$ abelian and every abelian normal subgroup finite Let $G$ be a group such that  $G'$ abelian  and any abelian normal subgroup of $G$ is  finite. Show that $G$ is finite. I am reading an older physics book that my professor gave me. It is going over Coulomb's law and Gauss' theorem. However, the book gives both equations with an $r^3$, not $r^2$, in the denominator. Can somebody please explain why it is given as r^3? An image is attached for reference.  Also for equation 1-24, can somebody please explain how the middle side is equal to the right side with the del operator? How should I punctuate around quotes where the punctuation required by the quote interferes with the punctuation of the sentence? The American convention in quotations is (typically) to place punctuation inside quoted text. But I always run into situations where the punctuation of the quote interferes with the punctuation of the sentence. How would you punctuate this (American, non technical)?     When my friends ask, "What do you want for your birthday?", I never know how to respond.   It seems odd to place the last comma outside the quote simply because of the question mark. Is that the preferred (i.e. most often accepted) standard? Is this arthropod non-intrusive and recommended to be left alive? I am in Portugal (Lisbon) at the moment, and when leaving my room late at night (12 pm ~ 04 am) I usually face about 4 of these arthropods in the corridors:    (For reference, the "line" in the image is a standard separation on the floor. This particular example of the animal is a little smaller than a nail.) They seem to have quite variable sizes and walk primarily on ground. Also, as implicit above, they seem to be active primarily during the late night. (I don't see them much often, if at all, during the morning/afternoon.) They can be quite fast, but if left unharmed do not move much. They also appear to take shelter inside the walls.  From what I searched, it seems possible that they are centipedes. I've seen sites saying that they are useful to keep other less pleasant animals at bay. My questions are: What are those animals, and should I leave them be or not? What does the factorial of a negative number signify? I understand that the factorial gives the number of arrangements. For example: the factorial of zero i.e. an empty set ( doesn't occur) is 1.   As the empty set can be arranged only in 1 way - i.e. by filling nothing. Now, let's take an example: 5 distinct seats. How many ways 5 distinct seats can be arranged? - 5! ways i.e. 120.  So, basically, factorial gives us the arrangements. Now, the question is why do we need to know the factorial of a negative number?, let's say -5. How can we imagine that there are -5 seats, and we need to arrange it? Something, which doesn't exist shouldn't have an arrangement right? Can someone please throw some light on it?. I saw some research done on the formula - Having briefly looked at Haskell recently, what would be a brief, succinct, practical explanation as to what a monad essentially is?  I have found most explanations I've come across to be fairly inaccessible and lacking in practical detail. "You're too clever a man" Cannot make a static reference to the non-static method Repeat String - Javascript How do I identify which features have NULL attributes in the attribute table of a shapefile?  When i try [field]= 'NULL' it selects the features with value = 0 (see picture) What's the function of the "|" (pipe) operator? How do I install the Cinnamon Desktop? I have read that there is a new Gnome-2 like interface called Cinnamon produced by the Linux Mint developers.  Is this available for Ubuntu users - and if so how do I install it?