Can Denel be regarded as a monopoly in SA

hygrometers and hair thermometers (often found as part of hygrometers/psychrometers) can be used to measure humidity. barometers are used to measure atmospheric pressure, while anemometers are used to measure wind speed. so the 2nd and 4th choices should be the correct answers.

the answer to your question is,

old stone age.

-mabel < 3

answer; occurs if the conflict is recognized logically and intellectualized;