Q. A reservoir is in the form of a frustum DT a cone. It is 8 m across at the top and 4 m across at the bottom. If it is c m deep, then its capacity in m3 is (A) 176 (B) 196 (C) 200 (D) 110 Share with your friends Share 3 Manbar Singh answered this We have,diameter of the bigger end of frustum of cone = D = 8 mradius of the bigger end of frustum of cone = R= 82 = 4 mDiameter of the smaller end of frustum of cone = d = 4 mradius of lower end of frustum of cone = r = 42 = 2 mNow, height of frustum of cone, h = 6 mCapacity = 13πhR2 + r2 + Rr⇒Capacity = 13×227×642 + 22 + 4×2⇒Capacity = 44716 + 4 + 8⇒Capacity = 447 × 28⇒capacity = 176 m3 8 View Full Answer