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1. 2. Before you start: Have you done all the practice quizzes, including the one on sigificant figures? The
quizzes do not count formarks, and some of the quiz questions are quite hard. The quizzes are for
learning and these tests are for assessment. Because the course runs in onedemand mod... 

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Enter answer here 3. [#163] Sammy's height 1 point In the US, lengths are often measured in inches,
feet, yards and miles. Let's do some conversions. The definition of the inch is: 1 inch = 25.4 mm, exactly.
A foot is 12 inches and a mile is 5280 ft, exactly. A centimetre is exactly 0.01 m or 10 mm. S... 

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5. [#165] Adding vectors 1 point JA| = [B| = |C|. Further, A + B + C = 0. What is the angle between A and
B ? Express your answer in degrees, but do not include units. Example: for 30 degrees, write
"30". Important hint: draw one or two diagrams, with arrowheads on the vectors... 

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8. [#168] Such stuff as dreams are made of. 1 point How much of you is not vacuum? Outside of the
nucleus, an atom contains mostly empty space. Estimate the fraction of the volume of an atom that is
occupied by the nucleus. Assume that a typical atom has a linear dimension of about 0.1 n... 

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11. [#1611] Nor any drop to drink 1 point Estimate the mass of water on the earth. The density of water is
1000 kg . m . Here are some approximations you can use: Compared with the oceans, lakes and rivers
are tiny. Clouds have very low density. There is (still) lots of ice in the polar regions, but mu...