2019-2020
1 ,
A , ,
B
C ,
D , , ,
2 11 19 2018 20
A
B
C
D
3 10ms
A10 m B 20 m C 30 m D 40m
4 x t x=5t t2
A
B
C 0
D 1m/s2
5 0-4s - , ( )
A
B 2s 2s
C2s
D4s
6