3 A car travels along a straight road with constant acceleration \(a \mathrm {~m} \mathrm {~s} ^ { - 2 }\). It passes through points \(A , B\) and \(C\); the time taken from \(A\) to \(B\) and from \(B\) to \(C\) is 5 s in each case. The speed of the car at \(A\) is \(u \mathrm {~m} \mathrm {~s} ^ { - 1 }\) and the distances \(A B\) and \(B C\) are 55 m and 65 m respectively. Find the values of \(a\) and \(u\). [6]