When resolving ns1.jiasule.net., here is the response from e.gtld-servers.net. (192.12.94.30) - dig @192.12.94.30 ns1.jiasule.net to reproduce: ;; OPT PSEUDOSECTION: ; EDNS: version: 0, flags:; udp: 4096 ;; QUESTION SECTION: ;ns1.jiasule.net.       IN  A  ;; AUTHORITY SECTION: jiasule.net.        172800  IN  NS  ns1.jiasule.net. jiasule.net.        172800  IN  NS  ns2.jiasule.net.  ;; ADDITIONAL SECTION: ns1.jiasule.net.    172800  IN  A   113.207.76.78 ns1.jiasule.net.    172800  IN  A   117.21.219.80 ns2.jiasule.net.    172800  IN  A   113.207.76.78  I'm asking A record for ns1.jiasule.net., and it tells me the name server for ns1.jiasule.net. is ns1.jiasule.net. with the A record on the ADDITIONAL SECTION. I do not understand why it does not return directly the A record in the ANSWER? I understand the role of the TLD servers is to provide the authority for the domain requested, but in this case, it would mean &quot;Go and ask to the IP of ns1.jiasule.net. to ns1.jiasule.net.?
This is a  about DNS glue records.   What exactly (but briefly) is a DNS glue record?  Why are they needed and how do they work?
What is going on in front of and behind a fan? Why is it that when you drop paper behind a fan, it drops, and is not blown/sucked into the fan, whereas if you drop paper in front of a fan, it is blown away? I'm flying Etihad Airways to Melbourne and I've a 14 hours layover at Abu Dhabi.  Some say that as long as you are inside the airport terminal you don't require a transit visa while some say you need a transit visa if your layover is more than 10 hours.  Can I stay inside the airport without a transit visa? Let $A \times \emptyset = \{(x,y)| x\in A, y \in \emptyset \}$. We know there is no element in $\emptyset$. But how does it follow that $A \times \emptyset = \emptyset $? Get bytes from std::string in C++ I'm working in a C++ unmanaged project.  I need to know how can I take a string like this "some data to encrypt" and get a byte[] array which I'm gonna use as the source for Encrypt.  In C# I do    for (int i = 0; i &lt; text.Length; i++)     buffer[i] = (byte)text[i];   What I need to know is how to do the same but using unmanaged C++.  Thanks! Why does blowing on someone who is wet feel colder than on someone who is dry? Kepler problem in time: how do two gravitationally attracted particles move? Two particles with initial positions and velocities $r_1,v_1$ and $r_2,v_2$ are interacting by the inverse square law (with G=1), so that  $$ {d^2r_1\over dt^2} = - { m_2(r_1-r_2)\over |r_1-r_2|^3} $$ $$ {d^2r_2\over dt^2} = - { m_1(r_2-r_1)\over |r_1-r_2|^3} $$  (the inverse square law along the line of separation). What is the complete solution of these differential equations? What is the position of the two objects as a function of time?  After reading a lot on Wikipedia, I've come to the definition of center of mass and relative coordinates:   $$R(t) ~=~ \frac{m_1 r_1 + m_2 r_2}{m_1+m_2}$$  $$\ddot{r}(t) r(t)^2 ~=~ (m_1+m_2)G$$  Where $R$ is the center of mass, and $r$ is the displacement between the particles... Is this correct? How do I proceed to solve the differential equation? How do they decide Blu-ray/DVD release date? I think my question is different from .  Some movies' productions release Blu-ray/DVD so early after theatrical release, others will take time. How do they decide for the Blu-ray/DVD release date? Local translations in curved spacetime A global Poincare transformation on a scalar field induces  $$\delta(a, \lambda)\phi(x) = [a^{\mu}+\lambda^{\mu\nu}x_{\nu}]\partial_{\mu}\phi(x). \tag{11.46}$$  In curved spacetime we replace $a^{\mu} \rightarrow \xi^{\mu}(x)$, but I read that in fact this new spacetime dependent parameter $\xi^{\mu}$ eats up the effect of the "orbital part of global Lorentz", so that in fact $\xi^{\mu}(x)=a^{\mu}(x)+\lambda^{\mu\nu}(x)x_{\nu}$, and we effectively have to treat $\xi^{\mu}$ and $\lambda^{ab}$ (the spin part of Lorentz) as the basis for gauge transformations.  I don't understand why this should be, any comments that might help? Why does the new local translation parameter include the effect of what globally used to be rotations/boosts?  References:   D.Z. Freedman &amp; A. Van Proeyen, SUGRA, 2012; p. 225. So I've been pulling my hair out over this for the last couple days now, I can't seem to find any solutions that work. I've fresh installed Ubuntu Gnome 16.04 on my system which has no other OS's running on it. Everything's fine aside from the fact that the default Nouveau display driver seems to be causing the UI to freeze sporadically every now and then. No problem right? Just install the proprietary drivers for my GPU and we should be golden? Well here's the thing, no matter how I try to get my GPU's drivers installed I always seem to hit some sort of issue. Here's what I've tried so far:   Switch to the proprietary driver from within the 'Software &amp; Updates' app in Ubuntu. For me the only option available is the 'NVIDIA binary driver - version 375.66 from nvidia-375 (proprietary, tested)'.    After selecting this driver it goes through the install process, asks me to 'configure secure boot' by entering a password, etc. This all seems to work fine initially until I reboot, but then before I see the login screen it seems to open a virtual terminal (usually accessed via alt+shift+F1), but then immediately boots me back to a black screen where it will flash this terminal for a split second every 4 seconds or so. I can access this terminal by using alt+shift+F1, and go on to use it as normal, but it will continually boot me back out to the black screen every few seconds. The only way I can solve this is to keep accessing the terminal each time it boots me out while I purge the nvidia drivers using sudo apt purge nvidia-*. After purging I'm then able to access the login screen and access my Ubuntu again as normal, besides having to reboot to presumably activate the Nouveau drivers again otherwise the resolution is all messed up and only one of my three monitors has anything displayed on it.    Using the steps listed  I download the latest stable/certified driver for my GPU (which as of writing this is version 384.69). However on step 3 where it instructs me to run the driver using sudo sh, I reach an issue where the installer informs me that I need to disable the Nouveau driver in order to continue. I've tried everything from uninstalling Nouveau using 'sudo apt-get remove --purge xserver-xorg-video-nouveau` to blacklisting Nouveau using the steps listed , by editing the 'nvidia-graphics-drivers.conf'.    Unfortunately no matter what I do to try and disable Nouveau the installer always informs me that the Nouveau driver is enabled and needs to be disabled in order to continue. What's funny is that I managed to install the driver using this method once before, but for the life of me I can't get it to work again.    Finally, I've attempted to install the driver by installing the PPA. I run sudo add-apt-repository ppa:graphics-drivers/ppa, sudo apt update, and finally going back into the 'Software &amp; Updates' app and select the 384.69 driver. However after going through the install process the same issue as described in my first method (1.) occurs.    I've also tried switching between gdm3 and lightdm with all 3 methods to no avail. I'm at a complete loss as to what to do. If anyone has any possible solutions I'd love to hear them, because right now I'm at the end of my tether.   If you require any further information just let me know and I'll be more than happy to provide it.   System info:   AMD FX-8350  Nvidia GeForce GT710 1gb  16gb RAM  Ubuntu Gnome 16.04 LTS What can cause a question to be bumped? What can cause a question to be "bumped" to the first page in the Active tab of a Stack Exchange site? (Changing the "Last Active" date.)  . Comma after introductory words, phrases, clauses: unacceptable, obligatory or optional? I am no native speaker and always confused about the comma in introductory phrases, in particular in prepositional phrases. Is there any hard rule when a comma must be set? If I make a google search for certain phrases, I often find both variants. Typical examples where I am not sure whether a comma must be set are:        First[ly][,] I must phone mother   In this case[,] we must...   For simple problems[,] the algorithm...   From Lemma 1.2[,] we obtain...   For a typical user[,] the algorithm...   In our theory[,] we...   A dark line on the horizon[,] the mountain range we were headed for seemed somehow not as threatening as when we had started out on the trip.   Avidly reading her novel[,] Jane did not notice that her stop was approaching.   To be sure[,] it is not easy to see a solution.   When you get to Rome[,] give me a ring. Add review queues to Android app I know there are some similar posts on adding review queues to the mobile web page. However, this is regarding the Stack Exchange Android app. I really would like to review posts and edits from the Android app, however this isn't included in the app yet. I'm not sure how it would be implemented; maybe there could be a button or something for review. Could we please see this? Chrome asks for password to unlock keyring on startup In Google Chrome, when I go to a login page, a window pops up asking to "Enter password for keyring 'default' to unlock". In most cases, whether I click Cancel or enter my password, the login form gets auto filled anyway.  How do I get rid of the popup? I want it to auto login each time, not ask for my system password. The dialog box never appears for any other apps. I have a dual monitor set-up. When I'm on YouTube, and I click the fullscreen icon, the fullscreen automatically goes to the second monitor. How do I get it to go fullscreen on my main monitor? I have an older Nvidia video card and my PC crashes when installing the driver for the video card in Ubuntu 16.04. When I get to the login screen but no further: after entering my password, the system went into a loop and returned always back to the login screen [with funny stripes present].   How do I fix this problem? show that a distance function is continuous Let $X$ be a metric space with metric $d$. Define $d: X \times X \to \mathbb{R}$, show that $d$ is continuous.  I would like to show that the function is continuous the topology way (since it is a course on topology).   Let $(a,b)$ be a basic open set in $\mathbb{R}$, then $d^{-1}(a,b) = \{(x,y): a&lt;d(x,y)&lt;b\}$. Define $A= \bigcup_{x \in X} B_{b} (x)$, where $B_b (x) = \{y \in X| d(x,y)&lt;b$}. Clearly $A$ is open. Now define $C = \{(x,y):d(x,y)&gt;a \}.$ Essentially I hope that $A \cap C$ is open. But I am stuck in showing that $C$ is open.  Any help please? :) Experimental Fractional scaling makes fonts dirty in Ubuntu 17.10 I updated to 17.10 from 17.04.   I activated the fractional scaling by running the following command.   gsettings set org.gnome.mutter experimental-features "['scale-monitor-framebuffer']"   Then, I changed 125% scale. The scale was changed, but the fonts and icons are so dirty.    The launcher icon and font in Google Chrome and other application except the system setting are dirty.  How can I resolve this problem?  For some reason, font in the system setting is not dirty... Can we mix dual-rank and single-rank DDR4 RAMs add transistor model to LTspice I'm trying to add the mmbt3904lt1g model to LTspice. - I've copied its data from the MMBT3904LT1.LIB.txt in the standard.bjt library. - I've added an NPN to my schematic then I've changed its value to mmbt3904lt1g  - through the Edit->spice directive I've pasted the path to this library I thought it was all to use this device but no simulation is achieved.. I get only: Can't find definition of model "MMBT3904LT1g"  where I'm doing wrong ? I've got a small piece of code that is parsing an index value to determine a cell input into Excel.  It's got me thinking...  What's the difference between   xlsSheet.Write("C" + rowIndex.ToString(), null, title);   and  xlsSheet.Write(string.Format("C{0}", rowIndex), null, title);   Is one "better" than the other? And why?