Espanol A researcher believes that 49% of people who grew up as the only child have an IQ score over 100. However, unknown to the researcher, this figure is actually 50%, which is the same as in the general population. To attempt to find evidence for the claim, the researcher is going to take a random sample of 400 people who grew up as the only child. Let p be the proportion of people in the sample with an IQ score above 100. Answer the following. (If necessary, consult a list of formulas.) (a) Find the mean of p. X (b) Find the standard deviation of p. 0 (c) Compute an approximation for P (p 20.49), which is the probability that there will be 49% or more people with IQ scores over 100 in the sample. Round your answer to four decimal places. Explanation Check