Answer to Question 1
Answer: B
Answer to Question 2
Answer: Puberty brings steady improvements in gross motor performance, but the pattern of change differs for boys and girls. Girls gains are slow and gradual, leveling off by age 14. In contrast, boys show a dramatic spurt in strength, speed, and endurance that continues through the teenage years. By midadolescence, few girls perform as well as the average boy in running speed, broad jump, or throwing distance. And practically no boys score as low as the average girl. Among boys, athletic competence is strongly related to peer admiration and self-esteem. Some adolescents become so obsessed with physical prowess that they turn to performance-enhancing drugs. Since 1972, high school girls sports participation has increased, although it still falls far short of boys. Girls get less encouragement and recognition for athletic achievement, a pattern that starts early and persists into the teenage years. Furthermore, daily free-time physical activity declines with age, more so for girls than boys. And at every age, only a minority of students engage in regular exercise outside of school hours. In high school, just 55 percent of U.S. boys and 48 percent of girls receive any physical education, with just 30 percent of all students experiencing a daily physical education class. Besides improving motor performance, sports and exercise influence cognitive and social development. Interschool and intramural athletics provide important lessons in teamwork, problem solving, assertiveness, and competition. And regular, sustained physical activitywhich required physical education can ensureis associated with lasting physical and mental health benefits.
Median Annual Earnings of Full-Time Workers, by Gender, 1960–2010
Changes in Time Spent with Family Members
Over time, cells acquire mutations. Two independently acquired mutations in the same cell may be suf
Time-of-entry mapping