College

**Q1:** How many significant figures are in the following measurement: 0.0009?

A. 1
B. 5
C. 4
D. 3

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**Q2:** Three unique samples are weighed on different scales at separate laboratories across the country. The first has a weight of 31.2 lbs, the second sample weighs 38.02 lbs, while the third measures 45 lbs. What is the total combined weight of all these samples?

A. 114.22 lbs
B. 110 lbs
C. 114 lbs
D. 114.2 lbs

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**Q3:** A track coach measures the 100-meter time of a track athlete. The runner completes the distance in 11.5 seconds. If the stopwatch has an uncertainty of 1.7%, what is the amount of uncertainty in the time?

A. 11.5 s ± 0.19 s
B. 11.5 s ± 0.20 s
C. 11.5 s ± 0.1955 s
D. 11.5 s ± 0.196 s

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**Q4:** The speed of a bullet train is measured to be 312.0 mph ± 3.9 mph. What is the percent uncertainty in this measurement?

A. 1.3%
B. 1.2%
C. 1.25%
D. 0.0125%