I have a working Xubuntu release 14.04 on my MacBook late 2007. The system suggests upgrading to release 16.04 LTS, but upgrading seems to not be working. My Mac has 4GB of RAM. Should I upgrade and how?
For a given hardware configuration, how do I find out if Ubuntu will run on it? What considerations should I take into account when choosing an Ubuntu version and  such as:    with a lighter desktop than the usual Gnome and Unity  with the even lighter LXDE desktop   Obviously Ubuntu does not run on some processor architectures. So how do I go about choosing the right version and derivate. How can I find out the minmal system requirements?
The output from the following script \documentclass{article} \usepackage{tikz} \usepackage{graphicx} \begin{document} \begin{tikzpicture}   \node(title)[text width = 0.25\textwidth, text height = 3 cm, draw]{title};   \end{tikzpicture} \end{document}  is  How can I vertically align the text in the node? Specifying the text depth as in \node(title)[text width = 0.25\textwidth, text height = 1cm, text depth = 1 cm, draw]{     title line 1\\     title line 2\\     title line 3};  Does not result in the text being vertically centred. "Welcome to emergency mode!" Think it is a fsck problem My computer booted to a black screen with this error message.  Welcome to emergency mode! After logging in,type "journalctl -xb" to view    system logs, "systemctl reboot" to reboot, "systemctl default" or ^D to    try again to boot into default mode.   journalctl -xb snippet (what I think is wrong):  -- Unit systemd-fsckd.service has begun starting up. juli 09 15:40:16 kim-SSD-Sationary systemd-fsck[414]: /dev/sdb1 contains a file system with errors, check forced. juli 09 15:40:16 kim-SSD-Sationary systemd-fsck[414]: /dev/sdb1: Inodes that were part of a corrupted orphan linked list found. juli 09 15:40:16 kim-SSD-Sationary systemd-fsck[414]: /dev/sdb1: UNEXPECTED INCONSISTENCY; RUN fsck MANUALLY. juli 09 15:40:16 kim-SSD-Sationary systemd-fsck[414]: (i.e., without -a or -p options) juli 09 15:40:16 kim-SSD-Sationary systemd-fsck[414]: fsck failed with error code 4. juli 09 15:40:16 kim-SSD-Sationary systemd-fsck[414]: Running request emergency.target/start/replace juli 09 15:40:16 kim-SSD-Sationary systemd[1]: systemd-fsck-root.service: main process exited, code=exited, status=1/FAILURE juli 09 15:40:16 kim-SSD-Sationary systemd[1]: Failed to start File System Check on Root Device. -- Subject: Unit systemd-fsck-root.service has failed -- Defined-By: systemd -- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel --  -- Unit systemd-fsck-root.service has failed. --  -- The result is failed. juli 09 15:40:16 kim-SSD-Sationary systemd[1]: Unit systemd-fsck-root.service entered failed state. juli 09 15:40:16 kim-SSD-Sationary systemd[1]: systemd-fsck-root.service failed. juli 09 15:40:16 kim-SSD-Sationary systemd[1]: Starting Remount Root and Kernel File Systems... -- Subject: Unit systemd-remount-fs.service has begun start-up -- Defined-By: systemd -- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel   I ignored other errors like: ACPI PCC probe failed, nvidia not proprietary, etc.  I can access my PC by pressing Ctrl+D , but it is annoying. What posts should be escalated to staff using [status-review], and how do I escalate them? How compatible are my old Nikon lenses? I'm looking at buying a new SLR body. I have an old film Nikon entry-level SLR (about ten years old) with a kit lens. If I buy a Nikon body, how likely is it that my old lens will work on it? Would I be better off buying a new lens? If we know the GCD and LCM of two integers, can we determine the possible values of these two integers? I know that $\gcd(a,b) \cdot \operatorname{lcm}(a,b) = ab$, so if we know $\gcd(a,b)$ and $\operatorname{lcm}(a,b)$ and we want to find out $a$ and $b$, besides factoring $ab$ and find possible values, can we find these two integers faster? java math calculation for coordinates of circle given radius of 1.00 I am able to solve simple differential equations like :  $$\dfrac{dy}{dx} = 3x^2 + 2x$$  We simply bring $dx$ to other site and integrate.  But how do we find solutions of differential equations like :  $$\frac{d^2x}{dt^2} + \dfrac{kx}{m} = 0$$  ?  We have been told the solution is $x(t) = A\cos ( \omega t + \phi_o)$ where $\omega\ =\sqrt{\dfrac{k}{m}}$  but how do we actually find it? I have:  \documentclass[a4paper,11pt]{report}   with no special customisation.  In one page, at the end of a section, I have a big figure with two paragraphs of text below it, and these two paragraphs are not enough to fill up the rest of the page.  When I use the \documentclass as above I get some extra white space at the end of the page, which is fine: the vertical spacing from the figure caption and between the two paragraphs is standard and correct.  But if I switch to:  \documentclass[a4paper,11pt,twoside]{report}   I get extra blank space between the figure caption and the 1st paragraph and also between the 1st and 2nd paragraph.  I want to use twoside to set the headings with fancyhdr. How can I get rid of these ugly white spaces? How do I redirect to another webpage? How can I redirect the user from one page to another using jQuery or pure JavaScript? Why didn't Harry himself drink Polyjuice Potion instead of all others in Deathly Hallows Part 1? In Harry Potter and the Deathly Hallows Part 1, it is shown that members of the Order of Phoenix come to rescue Harry from his house at Privet Drive. There, they all drink Polyjuice Potion and assume the form of Harry to confuse death eaters in identifying who is the real Harry.  An obvious, more safe, better choice would be to change Harry into someone else. Maybe a muggle, like his cousin Dudley. And then, safely take him to the Weasleys, maybe apparating. That way, death eaters won't ever find out. Isn't that correct?  Why didn't they take this path, and follow a rather complicated and risky one? What's the intuition behind the identities $\cos(z)= \cosh(iz)$ and $\sin(z)=-i\sinh(iz)$? I'm trying to understand in an intuitive manner the relationship between the circular and hyperbolic functions in the complex plane, i.e.:  $$\cos(z)= \cosh(iz)$$ $$\sin(z)=-i\sinh(iz)$$  where $z$ is a complex number.  From a geometric point of view, what I understand is that cos is the composition of a rotation through $\frac{\pi}{2}$, followed by cosh, and sin is the composition of a rotation through $\frac{\pi}{2}$, followed by sinh, followed by a rotation through $-\frac{\pi}{2}$ (where sin, cos, sinh, cosh are defined as complex functions).  Where does this connection come from? Is there some way it can be visualized in terms of complex mappings? (I'm not asking for a proof of the identities, I already know one). Dictionary for TeXstudio: “No dictionary Available” I have trouble spell checking my document in TeXstudio. When I press spellcheck, I get the error No dictionary Available. Am I supposed to install a dictionary separately? How? Any suggestion? Why didn't Count Dooku expose Palpatine? I have the message:   Error Broken count &gt;0 Check if you are using third party repositories. If so disable them, since they are a common source of problems. Furthermore run the following command in a Terminal: apt-get install -f Details: The following packages have unmet dependencies: firefox-globalmenu: Depends: firefox (= 19.0+build1-0ubuntu0.12.04.2) but 19.0+build1-0ubuntu0.12.04.1 is installed   Any suggestions? Does a passive Perception (Wisdom) check add WIS mod + Perception skill? I'm new to D&amp;D. There seems to be a discrepancy between the 5e Starter Set Rulebook and the associated character sheets. The Rulebook says that a passive wisdom (percep) score is "10 + the creature's wisdom modifier, as well as any bonuses."  In the example they have a 1st-level character (with a proficiency bonus of +2) Wisdom of 15 (+2) and a  proficiency in Perception, he or she has a passive Wisdom (Perception) of 14 (10+2+2).  But the Human Fighter Folk hero character has a WIS mod of +1, and a +3 written beside perception, and a passive Wis percep of 13 (not 14?).  The Dwarven Cleric has Wis mod of +3 and a +3 written beside perception, and only a 13 passive wisdom.  I guess this has to do with proficiency in the skill, but I'm confused. Can someone explain these instances and maybe also when proficiency is used, vs when just the modifier or just the skill without proficiency? How do I properly use the "Not an Answer" flag? What is the "Not an Answer" flag and what is its purpose? When should I use this flag? When should I not use this flag? But I'm still not sure if I'm using the flag correctly... An answer is "Not an Answer", but the flag was declined or disputed!   See also: Every time Windows 10 runs updates (which I see no way to control), it updates my graphics driver.  I like the old one because it is faster.  So, I have to reinstall it.  This is getting to be a pain.  Is there any way to stop Windows 10 from updating it again? How to change permissions of multiple files found with find command? Possible Duplicate:          On Wikipedia, it says that:     Matrix representation of complex numbers   Complex numbers $z=a+ib$ can also be represented by $2\times2$ matrices that have the following form: $$\pmatrix{a&amp;-b\\b&amp;a}$$   I don't understand why they can be represented by these matrices or where these matrices come from. Install GNOME Shell extensions from terminal Is there a way to install GNOME extensions from terminal, for example dash to dock? The way I do it now is to go into Ubuntu Software app store and install it.