CHAPTER 1
-------------
5. 0.6 %
12. a) 0.2866 m, b) 0.000085 V, c) 0.000760 kg, d) 0.000 000 000 060 s,
    e) 0.000 000 000 000 0225 m, f) 2500 000 000 V.
20. a) 1 km/h = 0.62137 mph, b) 1 m/s = 3.2808 ft/s, c) 1 km/h = 0.2778 m/s.
26. 500 h.
37. about 0.2 mm to 0.4 mm.
38. 1 hectare = 2.47 acres   
   [Using precise number: 1 acre = (1 mile^2)/640 = 43560 ft^2.]
46. 1000 days.
48. about 3 km radius.


CHAPTER 2.
--------------
2. 36 minutes.
4. 35 mi/h = 56 km/h = 15.6 m/s = 51 ft/s.
7. a) 260 km, b) 77 km/h.
16. 4.3 m/s^2.
18. 5.2 s.

--

21. 2.0 m/s^2,  114 m.  (starts with a "1" so keep an extra digit.)
24. 4.41 m/s^2, 2.61 s.
27. 348 m/s^2 = 36 g.
35. a) 8.8 s, b) 86 m/s.
39. 5.61 s.
69. 29.0 m.


CHAPTER 3. 
-------------
2. 10.2 blocks at 11.3 degrees North of East.
6. (11.9, -11.8, -4.4), magnitude = 17.3
8. a) V1=(-6.6, 0)u, V2=(6.0, 6.0)u.  b) 6.0u at 5.7 degrees left of y-axis.
10. a) sum=(24.0, 11.6), 
    b) magnitude = 26.7, direction = 25.8 degrees above +x-axis.
11. difference = (38.8, 51.7) 
    magnitude = 64.6, direction = 53.1 degrees above +x-axis.
37. 1.80 m/s at 19 degrees to the river current.
55. horizontal = -4.7 m/s^2, vertical = -2.9 m/s^2. 
58. 111 km/h at 37.0 degrees North of East.

--

19. 12.5 degrees or 77.5 degrees.
21. 7.92 m/s.
24. a) 9.60 m/s, b) 0.80 m longer.
27. 5.7 s early or 286 m before the target.
31. a) 10.4 s, b) 541 m, (51.9, -63.1) m/s, d) 81.7 m/s,
    e) 50.6 degrees below horizontal, f) 78 m above the cliff.