How Do You Calculate Angle and Velocity in Particle Motion Analysis?

[Daretodaredar]

Homework Statement

the position "r" of a moving particle moving in an xy plane is given by r=(2.00(t^3) -5t)î+ (6.00-7.00(t^4) )j with r in meters and t in seconds. In unit notation calculate:
A) R
B) Velocity
C) R when t is 25 seconds
What is the able between the positive direction of the x-axis and a line tangent to its path at t=25 s

Homework Equations

I have no clue what to do!

The Attempt at a Solution

 

[berkeman]

Homework Statement

the position "r" of a moving particle moving in an xy plane is given by r=(2.00(t^3) -5t)î+ (6.00-7.00(t^4) )j with r in meters and t in seconds. In unit notation calculate:
A) R
B) Velocity
C) R when t is 25 seconds
What is the able between the positive direction of the x-axis and a line tangent to its path at t=25 s

Homework Equations

I have no clue what to do!

The Attempt at a Solution

Welcome to the PF.

What is "unit notation"?

And surely in the Relevant Equation section, you could list the method for converting from rectangular to polar notation, since you are asked to find an angle. And what is the relationship between the position R(t) and the velocity V(t) in general?

You need to show some effort on your schoolwork questions, if you want to receive tutorial help here.