The position of an object is described as x = 4.0t and y= 1.5t2 - 2t + 1.0.

All factors are in SI-units.
a) What is the begining velocity of the object?
b) What is his acceleration?
c) What is the direction along the x-axe at the time t=1.0 s ?

Given answers are: 4.5 m/s in -27 degree; (0; 3.0 m/s2); +14 degree

Can someone please explain for me how to calculate these questions? I have no idea how to get these answers.