A particle's position $($in centimeters$)$ at time $t($in seconds$)$ is defined by the function $s(t)=3t^2+3.$ For part A $,$ find the instantaneous velocity of the particle at time $t=2.$

Answer parts A$-$B$.$

A$.$ What is the instantaneous velocity of the particle at time $t=2?$

Velocity $=$

B$.$ What is the correct unit for the velocity answer in part A$?$

Velocity units: $$ Select an answer $vv$

Your answer should be accurate to at least $2$ decimal places.