Refer to the Process Safety Progress (Sept. 2004) study of toxic chemical incidents in Taiwan, Exercise 3.5.
a. Find the probability that the incident occurs in either a chemical or nonchemical plant.
b. Find the probability that the incident did not occur in a school laboratory.

Data from Exercise 3.5 

Process Safety Progress (Sept. 2004) reported on an emergency response system for incidents involving toxic chemicals in Taiwan. The system has logged over 250 incidents since being implemented in 2000. The accompanying table gives a breakdown of the locations where these toxic chemical incidents occurred. Consider the location of a toxic chemical incident in Taiwan.

Location Percent of Incidents School laboratory 6% In transit 26% Chemical plant 21% Nonchemical plant 35% Other 12% Total 100%