Question

Mary slides down a snow-covered hill on a large piece of cardboard and then slides across a frozen pond at a constant velocity of 2.50 m/s. After Mary has reached the bottom of the hill and is sliding across the ice, Sue runs after her at a velocity of 4.30 m/s and hops on the cardboard. How fast do the two of them slide across the ice together on the cardboard

Answer 1

Explanation is in the file

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