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Question 1 A dumbbell with two equal masses m and a massless connecting rod of length D is rotating clockwise in the plane of the page at an angular speed of ω about a frictionless axle at its center. The axle is fixed in the ground and the dumbbell rotates freely around it. Also it the plane of the page, a projectile of mass M is fired horizontally at the dumbbell, sticking to one end. After the collision the dumbbell (with the projectile attached) is stationary (ie. neither rotating nor translating) 1) Which of the following are conserved during the collision and why or why not: energy, linear momentum, angular momentum 2) What was the speed v of the projectile before the collision?