At time t is equal to two, the town's population is 1,200 people. What is the town's population at t is equal to seven? Which expression can we use to solve the problem? So they don't want us to actually answer the question, they just want us to set up the expression using some symbols from calculus. So why don't you pause this video and try to think about it. So let's just remind us what they've given us. They've given us the rate function right over here.