to what volume should you dilute 20 mL of a 10 M H2SO4 solution to obtain a 0.130 M H2SO4 solution?

Answer 1

You want to change the concentration by a factor of .13/10 = .013, so you need to increase the volume by 1/.013 = 76.92

So, 20 * 76.92 = 1538ml