A poll agency reports that 52% of teenagers own smartphones. A random sample of 140 teenagers is drawn. Round your answers to at least three decimal places as needed.

a. Find the probability that more than 45% of the sampled teenagers own a smartphone

.b. Find the probability that the proportion of the sampled teenagers who own a smartphone is between 0.3 and 0.45.

c. Would it be unusual if less than 45% of the sampled teenagers owned smartphones?