please answer all the questions

7) Suppose firm knows that 30% of all workers are of high ability. If a firm knows a worker's ability, workers of low ability are paid $60,000 and workers of high ability are paid $100,000. a) (4 points) If the firm cannot differentiate what wage rate it is willing to pay? (Assume risk-neutral firm). b) (6 points) Firm assumes that a college degree can work as a signal that worker is of high ability. The cost of the degree is $20,000 for high ability worker and $30,000 for low ability worker. Find the type of equilibrium (pooling or separating), equilibrium strategies and payoffs