Solve the problem by using two equations with two variables.A barge takes 3 hours to move (at a constant rate) downstream for 21 miles, helped by a current of 2 miles per hour. If the barge's engines are set at the same pace, find the time of its return trip against the current.
A. 5 hours
B. 42 hours
C. 3 hours
D. 7 hours
Answer: D
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Use a tree diagram showing all possible results when a die is rolled twice. List the ways of getting the following result.The sum of the numbers showing is 5.
A. (1,4),(2,3),(3,2),(4,1) B. (2,3),(4,1) C. (2,3),(3,2) D. (3,2),(4,1)
Reparametrize the curve with respect to arc length measured from the point where t=0 in the direction of increasing t.
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Solve the problem.At a certain baseball diamond, the distance from home plate through the pitcher's rubber to the far wall (i.e., to dead center) is 416 feet. Given that the infield forms a square 90 feet on each side, how far is it from third base to dead center. Round your answer to the nearest tenth.
A. 483.8 ft B. 455.7 ft C. 358.1 ft D. 393.3 ft
Solve.The gravitational attraction A between two masses varies inversely as the square of the distance between them. The force of attraction is 2.25 lb when the masses are 4 ft apart, what is the attraction when the masses are 6 ft apart?
A. 4 lb B. 1 lb C. 3 lb D. 2 lb