Calculate the energy needed to vaporize 10.0 kg of iron (C = 0.110) initially at 2,640°C. heat =
16,300
110
Kcal

i think the answer is a, hope this is right, that would be my best guess.

scientific laws are the result of testing theories and proving them to be facts.

luster is not a good characteristic to use by itself because luster is the property of minerals that indicates how much the surface of a mineral reflects light. the luster of a mineral is affected by the brilliance of the light used to observe the mineral surface.

it's when something is going so fast it makes a loud noise, breaking the sound barrier, for example: a jet makes a loud noise, not only cause of the jet but because they reached a point where they went so fast that you can year the noise from various parts, kinda like a police car, lets say the car was going   so fast that you hear the siren of the cop car right next to you, but the car is probably a mile a way, it's cos the siren was next to you a few seconds if you understand me