How do I work this out ?

1) The energy, E, expended by a swimming dolphin, is proportional to the fourth power of the speed, v of the dolphin. (a) (4 points) Write a formula for E as a function of v. (b) (2 points) A dolphin traveling at 12 units expends 17 units of energy. Find the constant of proportionality, k. 2) The table below gives the total production of bicycles, B, in millions in the world at time t from 1950 to 2000. Year 1950 1960 1970 1980 1990 2000 Bicycles 11 20 36 62 92 101 dA (a) (4 points) Estimate - at t = 1970. (b) (4 points) Find a better estimate for dA If at t = 1970