Question 9-10 are based on the following description

Question 9-10 are based on the following description The random variable time to failure (TTF) follows Weibull distribution with scale and shape parameters =1 and =0.5, respectively. 9) The mean time to failure (MTTF) of that random variable is a) 2 b) 1.67 c) 0.893 d) 1.3 10) The reliability of the system at time (t)=5 months is a) 0.23 b) 0.55 c) 0.36 d) 0.11