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Which expression calculates the speed in meters per second of an object that travels a distance of 100 m every 20 seconds

The product of two negative rational numbers is always zero sometimes zero never zero

The sixth grade art students are making a mosaic using tiles in the shape of right triangles.each tile has leg measures of 3 centimeters and 5 centimeters.i f there are 200 tiles in the mosaic what is the area of the mosaic.