Approximately how many interneurons are contained in the human central nervous system?

During phase one of the 1966 Robbers Cave study, the separate groups developed group membership and solidarity. During phase two:

a. the boys began a series of cooperative events across the groups. b. the boys began a series of competitive events between the groups. c. hostility between the two groups of boys decreased. d. the groups failed to illustrate the ingroup-outgroup bias expected by Sherif.

In the United States, how many mothers have breastfed their babies at some point?

A) more than 75% B) 75% C) 50% D) less than 50%