Calculate the speed of an iceberg driven by wind on its exposed (not submerged) surface. Model the iceberg as a cylinder with 1/9 of its length exposed to wind and the rest submerged in water (assumed zero mean velocity in the water). If the wind is blowing with speed V, calculate an expression for the speed of the iceberg, U, as a function of the diameter of the iceberg/cylinder and all other physical properties that play a role in this problem.