An insurance company has a portfolio of two$-$year policies. Aggregate annual claims rom

the portfolio follow an exponential distribution with mean $25.$ Claims are independent of

each other. Annual premium of $30$ is received under the policies. Premiums under the

policy are received at the start of the year and all claims are paid at the end of the year.

Calculate the probability that the insurer is not ruined by the end of the second year,

assuming the insurer started with zero capital at the start of year $1.$