A screw-jack used to lift a bus is a A) first order lever
B) second order lever
C) pulley
D) screw

Keneila is attempting to ski down a 20 m high friction free hill for the first time. she has a speed 10 m/s at the top. what is her kinetic energy when she is a the bottom, 20 m ? (a)2500 j (b)9800 j (c)12300 j (d)3100j (e)15000j

Describe the path of a ray that approaches a mirror parallel to the principal axis.

If a substance is in the gas phase, which of qualities of the gas will stay constant? a: volume b: mass c: shape d: position of particles