Which of the following line spacing is invalid

Which of the following will NOT save your document ?

Pressing the TAB key while the insertion point is in the last cell of a table will :

I want to type the word ‘tired’ too many times in a document. But I don’t know what other words to use instead of ‘tired’. Which tool helps to find the alternative word ?

Auto Correct can detect and correct:

The option for changing Page orientation of a document from portrait to landscape is :