Final yield at the end

Dependence of final yield at the end on deposit

Mr. Zlámal is going to invest 8 000 EUR during one year at term deposit with annual interest rate 2,5 %.
How much money does bank pay off for Mr. Zlámal after one year?

deposit = 0 (slider from 0 to 1000, step 10)
tax = 0 (slider from 0 to 50, step 1)
interest = 0.5 (slider from 0 to 25, step 0.1)
a: y = deposit + deposit * (100 - tax) / 100 interest / 100
b: y = x + x interest / 100 * (100 - tax) / 100
c = false
d = false