Please help !! i’ll give 5 stars if help.

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

An advertising firm has an old computer that can prepare a whole mailing in 6 hours. with the of newer model the job is complete in 2 hours. how long would it take the newer model to do the job alone?

Ineed me i stuck and i don’t want to get it wrong