how can do i write a program that caculates federal tax, FICA tax and state tax and calculates estimated tax.

I'm taking a class on how to make a movie, and it offers some apps that would be in the process. the thing is, i don't have any of those ha. if you have any tips on some apps i could use, that would be awesome. i don't have an iphone, so don't suggest any apps like imovie. i know that this is a weird question, but it would be super for me. : )

Which of the following physical laws can make the flow of water seem more realistic? a. motion b. gravity c. fluid dynamics d. thermodynamics

2. fluorine and chlorine molecules are blamed fora trapping the sun's energyob forming acid rainoc producing smogod destroying ozone molecules