To calculate the change in temperature, subtract the initial temperature from the final temperature. Example: 84.2 degree Fahrenheit - 41 degrees Fahrenheit = 43.2 degrees Fahrenheit. The temperature from morning to afternoon changed by 43.2 degrees Fahrenheit.
It needs 12 volts so it will be the standard modern power supply provides 12 volts of power.
Electricity. The electrical supply is 230 volts /- 10%. The frequency of the supply is 50 hertz. The three-pin rectangular plug system is used, as in Britain. Adapters are very easy to find.