Which one would you weigh more if you traveled to two different planets that were exactly the same size/volume but one was made completely of iron and the other swiss cheese? explain.

The one with the greater gravitational pull would make you weigh more, so most likely the one made of iron will make you weigh more.

multiple allele inheritance is traits controlled by more than 2 alleles (ex: pigeons having 3 alleles of one gene govern their feather color).

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