1. A - II, B - III, C - I
2. a) t = s/v = 100m/(2m/s) = 50 s
b) 2 m/s = 2 × 0,001 km ÷ 1/3600 h = ok. 7,2 km/h
3. a) v = lambda/T = 90m/10s = 9 m/s
b) 9 m/s = 32,4 km/h
t = s/v = 1km/(32,4 km/h) = ok. 0,03 h = 1 min 48 s
4. lambda = v/f = 5 m/s ÷ 2 1/s = 2,5 m