In the following figure, rectangle represents Opticians, circle represents Curators, triangle represents Campers and square represents Europeans. Which set of letters represents Opticians who are either Europeans or Campers?
The mean of marks secured by 35 students in division A of class X is 65, 45 students of division B is 61 and that of 70 students of division C is 59. What is the mean of marks of the students of three divisions of Class X?