Consider a population with two types: helpers and slackers. Over time members of the population randomly interact in pairs. When two helpers interact, they each get payoff 20. When a helper and slacker interact, the helper gets 0 and the slacker 50. If two slackers interact, they each get payoff D, where D is some real number. If the growth rate of each type is proportional to average payoff, what will be the equilibrium population shares of each type? Note that your answer will depend on D