I have latest Ubuntu as of 5/6/2020. I have created bootable copy on usb stick to first try on Hewlett-Packard PACKARD desk computer.  Runs well!  Computer has qty 2 hard drives internal. Primary drive has Windows 7. I want to install UBUBTU on 2nd hard drive (500gb). I have 6gb ram and 6 processors, 64 bit .  How do I select 2nd drive?  altonddavisjr@yahoo.com is direct email.  When I selected to “”INSTALL””, the screens never gave me option to select correct hard drive.
I'd like to see the full How-To on how to use manual partitioning during Ubuntu installation. The existing guides (at least those I found here) cover only automatic part and leave untouched the manual part (or extremely short and contain no pictures).  I'd like to cover such situations:     If your disk contains other systems:
If a black body is a perfect absorber, why does it emit anything? I'm trying to start understanding quantum mechanics, and the first thing I've come across that needs to be understood are black bodies. But I've hit a roadblock at the very first paragraphs. :( According to :     A black body (also, blackbody) is an idealized physical body that absorbs all incident electromagnetic radiation, regardless of frequency or angle of incidence.   OK, that's nice. It's an object that absorbs (takes in itself and stores/annihilates forever) any electromagnetic radiation that happens to hit it. An object that always looks totally black, no matter under what light you view it. Good. But then it follows with:     A black body in thermal equilibrium (that is, at a constant temperature) emits electromagnetic radiation called black-body radiation.   Say what? Which part of "absorbs" does this go with? How can it absorb anything if it just spits it right back out, even if modified? That's not a black body, that's a pretty white body if you ask me. Or a colored one, depending on how it transforms the incoming waves.  What am I missing here? Anybody kindly help me to find how to calculate pressure in bar from flow rate. I have a pipe and from that I am transferring water at a constant flow rate of 5ml/min. At this flow rate, with a 0.5 cm diameter pipe, what will be the pressure generated by water? Homeomorphism that maps given points to given points bordermatrix with blocks I need to write a complicated matrix, that has a structure as in the attached picture. Calculating conditional entropy given two random variables I have been reading a bit about conditional entropy, joint entropy, etc but I found this: $H(X|Y,Z)$ which seems to imply the entropy associated to $X$ given $Y$ and $Z$ (although I'm not sure how to describe it). Is it the amount of uncertainty of $X$  given that I know $Y$ and $Z$? Anyway, I'd like to know how to calculate it. I thought this expression means the following:  $$H(X|Y,Z) = -\sum p(x,y,z)log_{2}p(x|y,z)$$  and assuming that $p(x|y,z)$ means $\displaystyle \frac{p(x,y,z)}{p(y)p(z)}$, then  \begin{align} p(x|y,z)&amp;=\displaystyle \frac{p(x,y,z)}{p(x,y)p(z)}\frac{p(x,y)}{p(y)}\\&amp;=\displaystyle \frac{p(x,y,z)}{p(x,y)p(z)}p(x|y) \\&amp;=\displaystyle \frac{p(x,y,z)}{p(x,y)p(x,z)}\frac{p(x,z)}{p(z)}p(x|y)\\&amp;=\displaystyle \frac{p(x,y,z)}{p(x,y)p(x,z)}p(x|z)p(x|y) \end{align} but that doesn't really help.  Basically I wanted to get a nice identity such as $H(X|Y)=H(X,Y)-H(Y)$ for the case of two random variables.  Any help?  Thanks A geometric reason why the square of the focal length of a hyperbola is equal to the sum of the squares of the axes? How do I make log4j clear a log at startup? Extracting tree crown areas from remote sensing data (visual images and LiDAR) First, if you have a better suggestion for title I'm really opened to suggestions, but it is the best I came up with.  If I touch an electric line and the earth, I will get electrocuted.  However, if I touch the positive of a car battery, people told me the same thing won't happen...why is it?  It seems I need to touch the battery positive and the battery ground. Is there a service that I can use to check if my machine will be able to run a certain game? How to change IP address to point to localhost? What is LookDev/Material Preview mode for in 2.8? How does quantum trapping with diamagnets work? I just saw  demonstration by someone from a Tel Aviv University lab.  What they achieved there is mind blowing. I myself own a levitron that uses the Hall effect to levitate a magnet, the problem with that is the magnet must always be flat facing the Hall effect base, any unbalance will wreck the levitation. But in the case of the video you can see that he isn't constrained by such things, the disk can levitate and stay still at whatever angle and orientation. Instead of being levitated, the disk is simply being held still.   How does this happen? He referred to this as quantum trapping, but I've little idea about what that is....  Also, what material is the base in these demos? Is the circular track in the demonstration magnetic? I assume this is so. Is there any conceivable way for this technology to make objects levitate on any surface? Why is file transfer speed decreased when copying multiple smaller files? Let's say I'm copying a portable apps directory from PC to an external HDD. An application.exe file is around 4 megabytes in size, but most other files are only tens of kilobytes in size, and most of those files take longer to copy/move than that bigger file having 4 megabytes.  Why is this? Can the Help action be used to give advantage to a specific ally's attack (rather than just the next ally who attacks the target)? I'm considering buying a solid state drive for my Unibody White MacBook 2010. The trouble is, I have no idea what to look for. What kind of connector am I looking for? (SATA?) What size? I'm told to get the kind that Apple uses so that I don't void my AppleCare warranty. What model/brand(s) would that be? How to get a tool that can only break specific blocks and has a name? Tutorial on how to back up my full Ubuntu desktop and files? I would like to be able to back up all my settings and files to a dedicated external hard drive in a way that makes (1) all the backup files accessible and (2) would allow me to restore my system is there is a crash.   Is there an app for this or any pointers?  Thank so much. By default  indents with a hard tab character. How do I change it to spaces? As the title says: Is a 1st-level spell cast using a 4th-level slot a 1st-level spell, or a 4th-level spell?