A manufacturer of semiconductors has a 10 % defect rate in the semiconductorsproduced

A manufacturer of semiconductors has a 10 % defect rate in the semiconductorsproduced. Every hour, fifteen semiconductors are selected at random and inspected for defects. If more than one defective in fifteen are observed, the process is stopped. 

(i) What is the probability that this process will be stopped within the next hour ? 

(ii) What is the variance of the number of defectives in a batch of 15 ?