Answer A) 0.2222 B) 0.8

Please answer step by step. Hand calculations I need. Dont use R code please.

Q4) Suppose the proportion of error in code developed by a programmer, which varies from software to software, may be looked upon as a random variable having the beta distribution with =2 and =7. (a) Find the mean of this beta distribution, namely, the average proportion of errors in a code from this engineer. (b) Find the probability that a software developed by this engineer will contain 30% or more errors. Ans: (a) =0.2222; (b) 0,8