Two dimentional motion question

[Nikolayevitc]

Hi everyone! I've just started to refresh my knoweldge of physics after a lot of time and I bumped into a question which I can't understand. I will really appreciate it if someone can solve and explain this thing for me. An image of the problem is attached to the thread. thx

 

[AsuraSky]

You're basically given two position functions that describe where the particle is at a given time and you have to find the velocity and acceleration of the particle given the position functions. Knowing that velocity is a derivative of position and that acceleration is a derivative of velocity will greatly help you in solving this problem.