Which option enables you to undo the last grammatical change?

How can you tell if someone sent you a text message to your email instead of a email

The basic work area of the computer is it screen that you when you first fire up your computer

Using a conditional expression, write a statement that increments numusers if updatedirection is 1, otherwise decrements numusers. ex: if numusers is 8 and updatedirection is 1, numusers becomes 9; if updatedirection is 0, numusers becomes 7.