What criterion is used to indicate the end of a time
period period/beginning of a new period

If you fill your car tire to a pressure of 32 psi (pounds per square inch) on a hot summer day when the temperature is 35°c (95°f), what is the pressure (in psi) on a cold winter day when the temperature is -15°c (5°f)? assume no gas leaks out between measurements and the volume of the tire does not change.