Would you please solve it real quick, that will be helpful and appreciated. Thank you. I will give you a good feedback too.

A pendulum consisting of a 2.0 kg ball on a 2.0 m long string swings back and forth so that (3mm,c = 5.00 . (a) How long does it take to complete 20 oscillations assuming no damping? (b) If the pendulum were in an elevator accelerating up at 4.0 mile2 would your answer to (a) be bigger, smaller or the same? Explain