\f3. In problems 3(a) and 3(b), find the error that was made in solving each implicit differentiation problem. Identify the error and explain what was performed incorrectly. (a) \f4. Choose one of the following two problems to solve. a) An oil tanker spills oil that spreads in a circular pattern whose radius is increasing at the rate of 20 feet per minute. At the instant the radius of the spill is 8 feet, how fast is the area of the spill increasing? b) A ten foot ladder leans against a wall. The lower end of the ladder is pulled away at the rate of 3 feet per second. At the instant that the top of the ladder is 7 feet above the ground, how fast is the top of the ladder coming down the wall