What keyboard shortcut selects an entire document?

Which of the following is recommended to reduce energy consumption?

A. Turning off peripherals when not in use B. Turning off monitors when not in use C. Turing off computer when not in use D. All the above

Write a void function called copy_to_screen that copies the contents of a file to the screen. The argument of the function is an ifstream object. Preconditions and postconditions follow: Preconditions: The stream argument for the function has been connected to a file with a call to the member function open. Postcondition: The contents of the file connected to the ifstream argument have been copied to the screen so that the screen is the same as the contents of the file. This function does not close the file.

What will be an ideal response?