To determine by how much the mass of the balloon will decrease if all the gas inside it escapes, we need to consider the mass of the gas initially present in the balloon.
According to the information provided, the balloon at the amusement park has 1,500 grams (g) of gas in it. If all of this gas escapes, the mass of the balloon will decrease by the mass of the gas that has escaped.
Therefore, if all 1,500 g of gas escape, the mass of the balloon will decrease by 1,500 g.
The correct answer to the question is:
1,500 g
