The executive branch is composed of the President, Vice President and Cabinet members. President The president is the head of state, head of the U.S. government and the commander-in-chief of the U.S. military.
Menarche. The average age of menarche, or first menstruation, in the United States is 12.88 years for Caucasian girls and 12.16 years for African American girls. A popular misconception is that menarche marks the beginning of puberty; in reality, menarche occurs later in puberty.
Today in the U.S., about 16 percent of girls enter puberty by the age of 7, and about 30 percent by the age of 8. In Europe, in 1830, the average age at menarche was 17. Similarly in the 1980s in rural China, the average age at menarche was 17.3 In the U.S. in 1900, the average was 14.2.