Do you have any idea how to get started? Do you have any work you can show?
I) you're given a magnitude and a vector in the direction of the force, what do you have to do to that vector to make it a directional vector? So what then is the resulting force vector?
II) you're given the coordinates of P, just turn this into a vector
III) you need to know the vector formula for a moment about a point given the force and the position vector. Look it up in your book.