What creative thoughts did rømer have to explain his measurements

A10.0 kg cart and a 15kg cart are locked together with a compressed spring between them. they are then released so that the spring pushes the two carts apart. the 10.0 kg cart is moving at 4.5 m/s afterward. how fast is the 15kg cart moving? 3.0 m/s 2.0 m/s 4.5 m/s 5.0 m/s

Heena wants to measure the volume of a ball that is 24 cm across. how should she set up her equation?

Zeros that follow non-zeros numbers and are also to the right of a decimal point are significant