Write 3 test cases for testing a pocket calculator?

TC1: Does the calculator turn on when teh on button is pressed TC2: Does itdisplay the number on teh screen that was pressed TC3: If we enter 2 and then the plus symbol "+" and then enter 2 again,then does it display the answer "4" or not. TC4: Same way for all the buttons like *,/,-,%, square roots and all TC5: When we press the clear button then is the screen display reduced to "0" or not