Use Probability for Trait Frequency Practice Test

A bacterial population contains two types: antibiotic-resistant (R) and antibiotic-susceptible (S). Before treatment, most bacteria are S. During antibiotic treatment, 90% of R bacteria survive, but only 5% of S bacteria survive. After treatment, what will most likely happen to the frequency of resistance in the population that regrows?

Hardy-Weinberg equilibrium is a baseline idea that allele frequencies stay the same when no evolutionary forces act. A mouse population had stable fur-color allele frequencies for many generations. Then a new predator arrives and mice with dark fur have a 70% chance to survive to reproduce, while mice with light fur have a 30% chance. What is the most likely outcome over the next several generations?