An industrial oven used to cure sand cores for a factory manufacturing engine blocks for small cars is able to maintain fairly constant temperatures. The temperature range of the oven follows a normal distribution with a mean of 450 degrees F and a standard deviation of 25 Degree F. Leslie Larsen, president of the factory, is concerned about the large number of defective cores that have been produced in the past several months. If the oven gets hotter than 475 degrees F, the core is defective.

a). What is the probability that the oven will cause a core to be defective?

b). What is the probability that the temperature of the oven will range from 460 degrees to 470 degrees F?