Assuming that the pressure and the amount of gas in the balloon are held constant, we can use the following formula to calculate the new volume of the balloon:
V2 = V1 x (T2 / T1)
where V1 and T1 are the initial volume and temperature of the balloon, and V2 and T2 are the final volume and temperature of the balloon.
Substituting the given values into the formula, we get:
V2 = 300 cm³ x (413 K / 353 K) = 350 cm³ (rounded to the nearest whole number)
Therefore, the new volume of the balloon will be approximately 350 cm³.