Experiments on learning in animals sometimes measure how long it takes mice to find their way through a maze. Only half of all mice complete one particular maze in less than 18 seconds. A research thinks that a loud noise will cause the mice to complete the maze faster. She measures the proportion of 40 mice that completed the maze in less than 18 seconds with noise as a stimulus. The proportion of mice that completed the maze in less than 18 seconds is . The hypotheses for a test to answer the researcher's question are a) H0: p = 0.5, Ha: p ≠ 0.5.
b) H0: p = 0.5, Ha: p < 0.5.
c) H0: p = 0.5, Ha: p > 0.5.