Answer:
a) he rate of change of the volume of a snowball (due to melting) is proportional to the square of the volume at time t. Initially, the snowball has a volume of 900 cm3
and V(0) = 900
where A is a real constant, it appears because it says that the change i volume (dV/dt) is "proportional" to . Furthermore, we should assume that A is a negative number, because the volume of the snowball will decrease as the time pasese by.
(b) For an insect moving along some path, the velocity at time t is proportional to the square root of its position.
Here again appears a constant B for the "proportional" part. And i wrote the velocity as "the rate of change of the position with respect to te time".