Need to know asap please ty

Find the value of x for which line a is parallel to line b

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.

Abox holds 500 paperclips. after a week on the teacher's desk 239 paperclips remained. how many paperclips were used?