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.
Girls are 12-13 years old, on average, when they get their first menstrual period (menarche), the committees note. That average age hasn't changed much in 30 years, though black girls go through menarche five months earlier than they did 30 years ago, according to the committees.