2
45
six
24 18
eight
six
1.5
Two. 2 pairs
6 pairs
All other errors
Three. four
six
eight
Answer; The quantity and time of daily transportation are inversely proportional, because the product of the corresponding quantities of these two changes is certain.
Four. 1 ... First, it can be proportional, directly proportional, because
Travel time = speed
2.. 1600 divided by 20- 150 divided by 20 = 5 (km/h) a —————————————
3..5×2.5= 12.5(km) Answer ——————————————————————.
Answer, write it yourself.