Ray BD bisects angle ABC, angle ABC = 5(x-6) and angle DBC = 2x+9 find the measurment for angle DBC

The line plot below represents the number of letters written to overseas pen pals by the students at the waverly middle school. each x represents 10 students. how many students wrote more than 6 and fewer than 20 letters. a.250 b.240 c.230 d.220