If you get a lint roller for christmas

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

Awave has a wavelength of 7 mm and a frequency of 19 hertz. what is its speed?

Examine the drawing of a molecule. each ring represents an atom of nitrogen (n). what’s the chemical formula of this substance?