A is located, as you look A is past -2 almost hitting -3 making the mark 2.8 so the answer is A
I think it’s 4 m because diameter is 2r
"At most 12" means "the highest we can go is 12". Think of it as the ceiling. So x can equal 12 or it can be smaller. This means 
<h3>Answer: Choice A</h3>