Which statement does NOT correctly compare silicon with another element

Ihave a density of 1.61g/cm^3 and a mass of 28g. find the missing value

A20 cm long spring is attached to a wall. the spring stretches to a length of 22 cm when you pull on it with a force of 100 n. what is the spring constant

Aball thrown by ginger is moving upward through the air. diagram a shows a box with a downward arrow. diagram b shows a box with an upward arrow. diagram c shows a box with a downward and upward arrow equal in size. diagram d shows a box with a downward and upward arrow with the downward arrow larger in size. which force diagram represents the forces on the ball? you may neglect the effects of air resistance.