Probability is a measure of how likely an event is to occur. Match one of the probabilities that follow with each statement of likelihood given. (The probability is usually a more exact measure of likelihood than is the verbal statement.) 00.010.450.500.550.991 (a) This event is impossible. It can never occur. (b) This event is certain. It will occur on every trial. (c) This event is very likely, but it will not occur once in a while in a long sequence of trials. (d) This event will occur slightly less often than not.