If cats are lactose-intolerant, how did we come to the belief that giving cats milk = good?

Cats are carnivores, meaning they depend entirely on meat and fat for sustenance. We add non-meat products to their food, such as grain/corn, but with enough protein and fat to nourish them properly, as well as a special chemical called "taurine," which is vital to a lot of different functions in the body. Cats cannot digest the sugar (lactose), but they go bananas over the fat. They enjoy the milk for the fat alone, but a cat doesn't know what "lactose intolerance" is. This then gives them the squirty poops, as it does with some people. Most people can see is that the cat loves it, so give it more. We do the same thing with our human children and candy. Terrible side effects, but they like the taste and cry for it, so give them more!

Why does breathing in through your nose and out through your mouth work so well during exercise?

So the reason it's advised to breath in through your nose and out the mouth is that it slows down the rate of breathing. If you breathe solely via your mouth, you run the risk of breathing too fast and reduce the efficiency of oxygen exchange (within the lungs, an exchange of oxygen/carbon dioxide happens at the blood level - if you breath too quickly, there might not be enough time for as much oxygen to bind as there could be. As a consequence, less oxygen is circulating to feed your muscles).
Try right now! Breathe swiftly for about 30 seconds and you'll soon notice yourself getting light headed (don't pass out though please).

TL;DR breathing through the nose slows down ventilation allowing more time for gas exchange

Why do pimples (zits) on the inside of your nostrils hurt so much more than any others?

The tissue inside your nose isn't very thick and has tons of specialized nerve cells right at the surface, which means that when a pore swells with infection (a zit), the skin is pulled tight and the pressure under the already thin tight skin pushes against all those nerves, causing signals to fire and increasing the painful sensation. Plus there just isn't much space in there.

How do corporate takeovers work? How does a company forcibly buy another?

Corporations have stock, which is ownership in the company. If you control enough of the stock then you own the company. If we take a simple company with 100 shares of stock the founder generally keeps 51 shares and sells 49 shares to investors. Say it looks something like this:

• Founder (F) - 51 shares
• Alice (A) - 20 shares
• Bob (B) - 20 Shares
• Charlies (C) - 9 shares

F has a majority so what he says goes. If later F needs cash for a divorce he may sell C 10 shares. F now has 41 shares but still has more than anyone else so he still runs the company. A may then go to C and buy those 19 shares off of him (giving her 29 shares) and go to B and buy 13 shares from him. Now A has 42 shares and F only has 41. A now owns the company whether F likes it or not.

How do companies decide whether to choose to list their IPO in NYSE or NASDAQ

The NYSE has very stringent requirements that make it tough for smaller companies to be listed on it. This is why we usually see the biggest companies on there.
NASDAQ is more friendly for start-ups and tech IPOs (Initial Public Offering). They still have lots of requirements but not as tough as NYSE.
A lot of companies start their public life in the OTC (Over the Counter) markets, then switch to NASDAQ or NYSE depending on their current financial strength. With the bigger IPOs, a company will start off on the NASDAQ and then switch to NYSE.
Why would they do this? Historically, the NYSE is the most trusted exchange for traders, which gives it a lot more volume.