If anyone could explain how the following problem is done, I'd be really grateful!

Given the acceleration vectora(t), the initial positionr(0) =r_0, and the initial velocityv(0)=v_0 of a particle moving in space, find the position vectorr(t) at time t.

a(t) = 6ti- 5j+ 12t^2k

r_0 = 3i+ 4j

v_0 = 4j- 5k