According to the video on nuclear power plants, what does pwr stand for?

PWR stands for many things. Since you're talking about nuclear power reactors I think PWR stands for pressurized water reactor.

A pressurized water reactor follows many steps but the main goal is to obtain thermal energy from water.

Hope it helped,

BioTeacher101

1. a)c-14 has two more protons

2. d)they have different numbers of protons, neutrons, and valence electrons; they are all gases at room temperature.

3. c) iron and nickel.

the answer is d.) potassium