Magnetic flux. Dont know where to start

[Anakrystine]

Homework Statement

A circular area with a radius of 7.90cm lies in the x-y plane.
A. What is the magnitude of the magnetic flux through this circle due to a uniform magnetic field B = 0.223T that points in the +z direction?
B.What is the magnitude of the magnetic flux through this circle due to a uniform magnetic field B = 0.223T that points at an angle of 52.8∘ from the +z direction?
C.What is the magnitude of the magnetic flux through this circle due to a uniform magnetic field B = 0.223T that points in the +y direction?

i don't even know where to start with this, I am completely overwhelmed

 

[Delta2]

You should look in your book for the definition of magnetix flux. If you ll understand the definition it would be easy to answer all 3 questions. The answer to each question is no more than a line.