At time $t=0 a particle starts travelling from a height 7 \hat{z} \mathrm{~cm} in a plane keeping z coordinate constant. At any instant of time it's position along the \hat{x} and \hat{y} directions are defined as 3 \mathrm{t} and 5 \mathrm{t}^{3}$ respectively. At t = 1s acceleration of the particle will be