Because Google Didn't Work

[BrokenQuill92]

1. Do landlords usually allow you to install extra locks on doors?

US specific laws must apply, so I won't comment. My guess is, no.

2. How do I change an air filter?

Air filter... for what? Air conditioning? Car engine? gas mask?

3. How do self cleaning ovens work?

I read about this a few weeks ago.
It seems there are a number of different technologies for self-cleaning ovens.
On all, it basically boils down to a coating on the walls of the oven. One prevents grease from sticking, period. Another has a special setting that causes a change in the coating and the grease falls off.... and those are the two main ideas.
Personally, I'd avoid self-cleaning ovens, as that coating can (and will, if Murphy's Law stands) fall on your food and something tells me it's not the most healthy substance around.

4. I don't know anything about hanging curtains!

There are, at least, two pieces that attach to the wall.
These two are used to hang the top bar.
The curtains must have some rings and that bar has to go through those rings at the moment of assembly... It can be tricky, if you're working near corners and the bits that attach to the walls have holes where the bar goes through... Some of them are open on top so that you can insert the bar in the curtain rings sitting down and then you just have to hang the bar on those wall mounts (there must be proper names for these pieces, but I don't know them)

A filter for a house. Oh no! There's filters for that other stuff too?! As I said, I'm a derp.