The very rigorous medical program at a local university has a 10% drop out rate for each year. if the school admits 1,000 freshmen, how many diplomas will need to be ordered 4 years later?

Which of the following can occur to two segments of a population if they are geographically isolated 1.) they can only share some types of genes 2.)both groups most likely become extinct 3.)they find a way to come back together 4.)eventually they become separate species