Probability with exponential

Colin's old radio set has two independent speakers, each of which relies on
three independent components. The lifetime of any component follows an
exponential distribution with parameter l  = 0.1 hours. A speaker will function
if at least two of its components are working.

(a) Find t such that the probability that the lifetime of a component is greater
than t is 0.01.

(b) Colin wants to listen to a play which is being broadcast on the radio and
lasts for two hours. What is the probability that both speakers on his
old radio will be working at the end of the play?

Thanks for the help

Throughout I assume that expected life of a component is 10 hrs (i.e parameter = .1)
a) Prob(life > t) = e^(-t/10) = .01 ===> t = 10ln(100) = 460.5 hrs
b) Prob(a speaker survives 2 hrs) = [e^(-2/10)]^3 + 3[1- e^(-2/10)][e^(-2/10)]^2
= .549 + .365 = .914