4. Consider the power dissipated by a resistor, P=I°R . Suppose we have a current of 1 amp and a resistance of 100 Ohms, and these values are exact. The power is then 100 Watts exactly. a. Suppose the current changes by +0.02 A and the resistance changes by -1 Ohm. These are changes in the current and resistance. Use partial derivatives to find the approximate change in the power and check this result by directly substituting the changed current and resistance. b. Now suppose the current has a tolerance of +/- 0.02 A and the resistance a tolerance of +/- 1 Ohm. Find the tolerance in the power dissipated.

4. Consider the power dissipated by a resistor, P=I°R . Suppose we have a current of 1 amp and a resistance of 100 Ohms, and these values are exact. The power is then 100 Watts exactly. a. Suppose the current changes by +0.02 A and the resistance changes by -1 Ohm. These are changes in the current and resistance. Use partial derivatives to find the approximate change in the power and check this result by directly substituting the changed current and resistance. b. Now suppose the current has a tolerance of +/- 0.02 A and the resistance a tolerance of +/- 1 Ohm. Find the tolerance in the power dissipated.