Your brother's mass is 40.0 kg, and he has a 1.30 kg skateboard. what is the combined momentum of your brother and his skateboard if they are going 8.50 m/s?

Independent variable is something that is changed in a experiment. 

Following the american gauge wire standards ,the larger gauge number, the slimmer the wire and thus the smaller current carrying capacity it can have.then both statements would be incorrect, as they are saying the opposite of what it is actually is.(smaller gauge numbers have thicker wires and can carry more current)

The correct answer is:   [b]:   "convection" .