4             Correct the mistakes in these sentences. Underline

one or two

incorrect word(s) and write   the correct word(s) on the line.

24           He

founded a problem with his computer. ________

25           Yesterday

afternoon he visit a client. ________

26           You

checked the spreadsheet carefully? ________

27           After

starting a new OS install, you should back up your computer. ________

28           A

stylus is an output device. ________

29           If

you divide eight by four, you get thirty-two. ________

30           There

is a problem with the formula in query B2 of the spreadsheet. ________