Dr. Andrews wants to study how many children under the age of 5 in the United States have been diagnosed with autism over the past 10 years. In order to do this, he is most likely to use a random sampling of the general population to estimate the prevalence of autism

Oscar is 5 years old. If he's an average child, you'd expect him to need approximately how many hours of sleep each day?

A) 6-7 B) 8-9 C) 10-11 D) 12-13

Above the cilia in the organ of corti is the _____ membrane that slides back and forth with the sound waves displacing the hair cells.

a) corti b) auditory c) vestibule d) tectorial