What does it mean when there is a 3 around a square root sign?

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Ablock of wood is a cube whose side is x in. long. you cut off a 1-inch thick piece from the entire right side. then you cut off a 3-inch thick piece from the entire top of the remaining shape. the volume of the remaining block is 2,002 in3. what are the dimensions of the original block of wood?

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