Please help me with the problem​

Create a question with this scenario you could ask that could be answered only by graphing or using logarithm. 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.

  cassidy wants to cut the yellow fabric into strips that are 0.3 yards wide. how many strips of yellow fabric can cassidy make? yellow fabric 16 yards for $108.00.

Which expression is equal to (f+g)(x)?