Refer to the Early Childhood Education Journal (Mar. 2014) study of interactions in a children's museum, Exercise 2.19 (p. 41). (Interactions by visitors to the museum included show and-tell, learning, teaching, refocusing, participatory play, advocating, and disciplining interactions.) Recall that the researchers observed a sample of 170 meaningful interactions, of which 81 were led by children and 89 were led by adult caregivers. 

a. Give a point estimate of the true proportion of all meaningful interactions in a children's museum that are led by children.

b. Form a 90% confidence interval around the proportion, part a.

c. Interpret the interval, part b, in the words of the study.

d. Suppose an educator claims that the true proportion of all meaningful interactions in a children's museum that are led by children is 35%. Make an inference about this claim.