[填空题]
You are the design engineer in charge of the 03-wzr+vf0qv: nkrb fe.tcmsr i2p8n ,lg4 l,cras+vc p78/cg 6)q 6 ngulwthjxl;hworthiness of new automobile models. Cars are tested by smashing them into fixed, massive barriers at 50km/h (30 mph). A new model of mass 1500 kg takes 0.15 s fromqw;gu6hn) 6l8cv jg7p x/l+tc the time of impact until it is brought to rest. (a) Calculate the average force exerted on the car by the barrier. $\approx$$a\times10^5$N a =
(b) Calculate the average deceleration of the car. m/$s^2$
