Afirm offers routine physical examinations as part of a health service program for its employees. the exams showed that 8% of the employees needed corrective shoes, 15% needed major dental work, and 3% needed both corrective shoes and major dental work. what is the probability that an employee selected at random will need either corrective shoes or major dental work?
a. 0.20
b. 0.25
c. 0.50
d. 1.00