Answer:
She needs to know the Mass and acceleration
Number of grams in 1 mole = 6.23 * 10^23
Now, in 20.50, it would be: 20.50 / 6.23 * 10^23 = 3.4 * 10^-24 moles
In short, Your Answer would be Option A
Hope this helps!
The frozen balloon shrank because the average kinetic energy of the air molecules in a balloon decreases when the temperature decreases. This makes the molecules move more slowly and have less frequent and weaker collisions with the inside wall of the balloon, which causes the balloon to shrink a little. This can be called contraction.