Radial and Tengential questions - Help

[nukeman]

Homework Statement

Here, I will just post the question as an image. Never mind the one where I have to sketch, but b and c I am having trouble with.

How do you calculate the radial and tangential aspects of the cars acceleration? and from that info, how do I calculate the radius?

Homework Equations

The Attempt at a Solution

The car is speeding up correct?

 

[nukeman]

Anyone?

Thanks, much appreciated!

 

[nukeman]

I am having trouble knowing how this sketch should look like?