V1=(V0+a t1)
s2 =V1+(1/2 a) 1*1 = (V0+a t1)+(1/2 a) 1*1
1.5=1.5a +V0
V5=(V0+a t5)
s6 =V5+(1/2 a) 1*1 = (V0+a t5)+(1/2 a) 1*1
3.5 = 5a +V0
联立上面2个结果,可以得到 a = 0.5 ,V0= 0.75