Kg*cm^2 /s^2 what does it represent

Which of the following elements is in the same period as phosphorus? a. carbon c. nitrogen b. magnesium d. oxygen select the best answer from the choices provided a b c d

The items in the following list are all units of matter. which is the smallest unit that retains the properties of the matter? a.) atom b.) compound c.) electron d.) element

If there's a small amount of friction between two surfaces, the result could be select all that applya. no movement b. heatc. a little bit of movementd. sliding around