Give yourself 15 minutes maximum. Write out answers. Then look at the solutions and grade yourself. I hope your got 80% right.

1. "milli" means divided by 1000 as in millimeter is a meter divided
by 1000. "pico" means divided by 10^{12}. If a molecule
moves a picometer in a millisecond, what is its speed in m/s (express as
a power of 10).

2. What is sin(45^{o}) (use an elementary mathematical expression,
not a calculator.) Do the same for sin(-45^{o}).

3. Consider the graph below. It shows the position of two different
objects as they change in time. Object A corresponds to the straight
line, and object B to the curved line.

a. Which object is ahead at time 0?4. Given that x + 3y = 20 and that 2x - y = 10, find x and y.

b. Which object has larger velocity at time t=2.5 s?

c. At what time (approximately) do the two objects have the same velocity?

d. What is the velocity of object A at t=4 s?

5. The clock says 10:00 o'clock. The sun, shown schematically below, is directly overhead (but very far away.) The hour hand (short hand) is 1.00 m long. How long is the shadow of the hour hand on the level ground below? Your answer should be a simple exact mathematical formula. If you don't get it that way, give a numerical result from your calculator for half credit

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