My question is very simple and yes I'm saying all this bc I can't ask without 20 words- What is 400 cubed?

I'm confused on this could anyone me and show me what i need to do to solve it.

Solve the equation for b: a= (1/2)(b)(h)

Jenny invests $2,000 at an interest rate of 5%. the amount of money, me, in jenny's account after tyears can be represented using the equation ma-2000(1.05). if jenny would have invested the same amount of money at the same interest rate four years ago, the equation representing the amount of money mo. in her account would be represented using the equation! mg = 2000(105)*** which of the following is equivalent to mp? 2000(105) om- 1.05 2000(1.05) mo 1059 mp-2000(1.05) (105) mp - 2000(1.05) + (1.05)