Write an alternative function to gen Kids () (see Section 7.3), called gen Kids B (), where the B stands for batch. In this function, generate the inter-arrival times in batches, where the size of the batch depends on the expected number of offspring for a job. The expected number depends on the rate λ and the birth and completion times of the parent. That is, for a job born at time α and complete at time β, we expect it to have (β - α) × λ offspring. The parameters to this function and their default values should be the same as gen Kids ().