[填空题]
A car starts rolling down a 1-in-e;qz;cptih+b. m )f yp6c 35jw4 hill (1-inn9k6pksmju 1(vbll(: -4 means that for each 4 m traveled along :lkukpsvm6( nlj(b9 1the road, the elevation change is 1 m). How fast is it going when it reaches the bottom after traveling 55 m? (a) Ignore friction.
(b) Assume an effective coefficient of friction equal to 0.10.
