If the volume of a gas container at 32.0°c changes from 1.55 l to 755 ml, what will the final temperature be?

Charles law states that volume of gas is directly proportional to temperature at constant pressure.

where V - volume and T - temperature 
parameters for the first instance are on the left side and parameters for the second instance are on the right side of the equation 
T1 - 32 °C + 273 = 305 K
substituting these values in the equation 

T = 149 K
temperature in celsius = 149 K - 273 = - 124 °C
new temperature is 124 °C

The answer is a) carbon-12