Chinese New Year Holiday HW

The lifetime of a battery is measured as 8.5 h, correct to the nearest 0.5 h. Which of the following CANNOT be the actual lifetime of the battery?

• 8.2 h

• 8.27 h

• 8.51 h

• 8.69 h

The length of a table is measured as 500 cm, correct to 2 significant figures. What is the percentage error of the measured length?

• 0.1%

• 0.2%

• 0.5%

• 1%

The length of a string is measured as 2.5 m and its relative error is 0.04. Find the maximum absolute error of the measurement.

• 0.05 m

• 0.1 m

• 0.2 m

• 0.5 m

• A = 12, B = 3

• A = 4, B = 8

• A = -4, B = 8

• A = -4, B = 6

• 81 – 36a²

• 36a² – 81

• 18 – 12a²

• 12a² – 18

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• -2r

• 6r

• -2r(2s – 3w)

• 6r(2s – 3w)

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