Can someone help me on this please

What is the volume of a rectangular prism if the length is 10.4 mm the width is 5 mm in the height is 8 mm

Stephen thublin invests $1,000,000 in a 45-day certificate of deposit with 6.55% interest. what is the total interest income from the investment?

Atheater wants to build movable steps that they can use to go on and off the stage. they want the steps to have enough space inside so they can also be used to store props. how much space is inside the steps?