1. I'm going to assume that y varies directly to x.

If y varies directly to x, then

K is the constant of variation. Find constant of variation using the numbers given in the question, then replace in the equation above. Then find y when x = -5.

2.

Given:

Using this given relation, you can find out how many feet are there in 1 mile:

Now, let's divide this into two parts.

a. Find how many miles are there in 1000 ft.

b. Find how how many hours in a second.

b. Substitute.

a.

b. There are 3600 seconds in an hour. So how many hours are there in one second?

Can you continue?