Kinetic energy and gravitational potential energy of a pendulum

A simple pendulum consists of a 2 m length rope and 3 kg bob. at one specific instant the bob has a speed of 4 m/s and the rope makes an angle of 30 degrees to the vertical.
a.) What is the pendulum's kinetic energy at this instant?
b.) what is the gravitational potential energy at this instant?

for the kinetic energy i got 24J but i can't figure out how to find the gravitational potential energy.can someone tell me what formula(s) work? i used PE=mgh but i dont think this is right.

I got 7.87777

mgh is used, the h is the displacement from the lowest point.
If you draw a diagram with the bob at its lowest point and at a 30 degrees offset, you can draw a right triangle, where the hypoteneuse is 2m, the angle is 30 degrees, and the adjacent side of the triangle is 2-h, where h is the height from the lowest point.

then,
cos30 = (2 - h) / 2
will give you the h that you need to put into mgh.

I got h = .26794m