Step-by-step explanation:
Gay-Lussac's law states that if P=pressure and T=temperature, then P/T=P/T. Temperature must be in Kelvin, but pressure can be in any unit.
To convert Celsius into Kelvin, just add 273: 10+273=283K, and 28+273=301K.
So using the equation,
200kPa÷283=? kPa÷301
Solving this equation gives you about 212.72 kPa.