Patrick B. answered 07/12/20
Math and computer tutor/teacher
velocity V(t) = integral A(t) dt = integral [ 6t+16] = 3t^2 + 16t + C
initial velocity v(0) = 6 ---> C = 6 , so v(t) = 3t^2 + 16t + 6
position s(t) = integral V(t) dt = integral ( 3t^2 + 16t + 6) = t^3 + 8t^2 + 6t + C
initial position s(0) = 14 ---> C = 14
s(t) = t^3 + 8t^2 + 6t + 14
s(7) = 7^3 + 8(7)^2 + 6(7) + 14
= 343 + 8*48 + 6(7) + 14
= 343 + 384 + 42 + 14
= 727 + 56
= 783