s=vt

s=s1+s2

s1=v1.t , s2=v2.t

s=v1.t+v2.t, s= (v1+v2)t

s=(80+60).3 km

s=140.3 km

s=420km

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2p-(3p-(2p-c)=2p-(3p-2p+c)=2p-(p+c)=2p-p-c=p-c

s=