Percentage or percent

Can a native speaker tell me which are correct please?

1 He's one percent/percentage/percentage point better than him. He's ranked 93, his opponent 94.
2The team shot 2 percent/percentage points worse than their opponent.
3 You have 5 percent of battery on your computer to finish up your work. I don't have the charger with me.

What percentage/percent of the movie has downloaded?

If using percentage in a question, you have to use percent in the answer right as in the following:

What percentage of women go back to work after giving birth?

20 percent go back to work.

How come in the question "percentage" is used and in the answer "percent"?

Thank you so much