. In an economy of 100 people in the labor force, if 10 people are unemployed for 4 weeks during the year, and 30 people are unemployed for 8 weeks during the year, and the rest are employed continuously throughout the year, then the average duration of unemployment in this economy is:A. 4 weeks. B. 7 weeks. C. 8 weeks. D. 20 percent.

option (B) 7 weeks

Explanation:

Data provided in the question:

10 people are unemployed for 4 weeks during the year

30 people are unemployed for 8 weeks during the year

Now,

The average duration of unemployment in economy

= ∑(Number of weeks × Number of unemployed) ÷ [Total number of unemployed]

= [( 4 × 10 ) + ( 8 × 30 ) ] ÷ [10 + 30 ]

= [40 + 240 ] ÷ 40

= 280 ÷ 40

= 7 weeks

Hence, option (B) 7 weeks

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.