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In 1932, Albert Dremel of Racine, Wisconsin, created his rotary tool that has come to be known as a dremel. Suppose a dremel starts from rest and achieves an operating speed of 36,000 rev/min. If it requires 1.40 s for the tool to reach operating speed and it is held at that speed for 47.0 s, how many revolutions & has the bit made? What is the average angular acceleration a; , for the start-up period? Suppose it requires another 8.10 s for the tool to return to rest. What is the average angular acceleration a3 ; for the slow-down period? How many revolutions 8y, does the tool complete from start to finish