Why did Davy hire faraday

What is the length of the missing leg in this right triangle? 18 mm 24 mm 26 mm 32 mm

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.

Which number line correctly shows 0.8 + 0.3?