Finding complex number from polar coordinates

Thanks for all the help on the previous problems, I figured out all my problems! Now, I'm stuck on another kinda simple area. Converting polar coordinates to complex numbers...

Give the complex number whose polar coordinates are

(a)

(b)

If someone could just walk me through one of the problems, I would greatly appreciate it! I have 6 of these to do, and I'm pretty sure I can figure them all out if someone can provide me with a walk-through on one! Thanks, and good night! zzzz