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Is each relation a function? if so, state whether it is one-to-one or many-to-one. 3. (-4,7), (-3,5), (1,4), (3,-8), (5,-11) 4. (-4,8), (-2,4), (0,1), (2,4), (4,8) 5. (-2, 1), (-2,3), (0,-3), (1,4), (3,1)

Twice the sum of a number and 4 is equal to three times the difference of the number and 7. find the number.

An air conditioning system can circulate 350 cubic feet of air per minute. how many cubic yards of air can it circulate per minute?