I need some help on some math problems please. I answered some of them so could you tell me if they are right and if not, how do I solve them to get them right?Also, the ones that I haven't answered or that are incomplete, please explain to me how to solve them

1. What number is 18% of 95?
My answer: 18x95=1710
1710/100= 17.1

2. Solve the percent equation for b.
Not sure about that one ^

3. 132 is 12% of what number?
Not completely sure on how to do that one either.

4. Length of movie projected at 24 frames per second: I=24f. Solve for F
I think it might be:
I=24f
f/I=24
Ixf/I=24xI
f=24I