PDF SUMMER MATH PACKET For Students Entering 6th Grade Math 79. B A circle measures 360o subtract all the measurements form this. 80. D 81. A Angle BCD = 180o so 180 - 60 = 120 82. A See terms page 83. B 84. A 85. C Sum of interior angles of a triangle is 180o and there are 3 triangles so 180 x 3 = 540