In a NiCd battery, a fully charged cell is composed of nickelic hydroxide. Nickel is an element that has multiple oxidation states and that is usually found in the following states:

Nickel Charge                        Proportions Found

0……………………………………………...0.17

+2…………………………………………….0.35

+3…………………………………………….0.33

+4…………………………………………….0.15

(a) What is the probability that a cell has at least one of the positive nickel-charged options?

(b) What is the probability that a cell is not composed of a positive nickel charge greater than +3?