Cyclobutane decomposes to according to the following equation: C4H8 → 2C2H4

The rate constant, k, for the first-order decomposition of cyclobutane, C4H8 at 500 °C is
9.20 × 10^-3 s-1

If the initial concentration of cyclobutane is .400 M, what will be the concentration after 1.50 x 10^2 seconds?

If the initial concentration of cyclobutane is .400 M and the concentration has decreased to .120 M, how much time has transpired?

What is the half-life of this reaction?

How could you change the rate constant, k, for this reaction?