Which expression is equivalent to (sf)(6)?
s(t(6))
s(x) xt(6)
s(6) * f(6)
6*s(x) * t(x)

David estimated he had about 20 fish in his pond. a year later, there were about 1.5 times as many fish. the year after that, the number of fish increased by a factor of 1.5 again. the number of fish is modeled by f(x)=20(1.5)^x. create a question you could ask that could be answered only by graphing or using a logarithm.