)the box plot shows the number of years during which 16 schools have participated in a marching band competition: a box plot is titled years of participation and labeled years. number line from 0 to 10 with primary markings and labels at 0, 5, and 10. the box extends from 3 to 7 on the number line. there is a vertical line at 5. the whiskers end at 1 and 10. at least how many schools have participated for 3 to 7 years?