The escalator steps move with a constant speed of 0.6 m>s. If the steps are 125 mm high and 250 mm in length, determine the power of a motor needed to lift an average mass of 150 kg per step. There are 32 steps.

The correct answer is  "c".  it is "c" because melting is an endothermic change, and endothermic get's energy from surroundings. 

The purpose of a lab is to do your "expirements" the importance of the topic is so you can now what the story is about and the last one is because no one is me with my question ( what is 3 over 4 x - 9 = 27 maybe you can )

Supply is the markets term for selling a specific quantity of products at various prices. the law of supply and demand is the one which affect the pricing and also the quantity the market is able to produce or make available.