There is a relation between an air-plane's weight x and the runway length L required for takeoff. For some airplanes the minimum runway length L in thousands of feet is given by L(x) = 3log.x, where x is measured in thousands of pounds.

(a) Evaluate L(100) and interpret the result. 

(b) If the weight of an airplane increases tenfold from 10,000 to 100,000 pounds, does the length of the required runway also increase by a factor of 10? Explain. 

(c) Generalize your answer from part (b).