What is the answer to the first one? pls help

Which equation represents a circle with a center at (–3, –5) and a radius of 6 units? (x – 3)2 + (y – 5)2 = 6 (x – 3)2 + (y – 5)2 = 36 (x + 3)2 + (y + 5)2 = 6 (x + 3)2 + (y + 5)2 = 36

Find the greatest common factor of -30x 4 yz 3 and 75x 4 z 2.

Icould really use some with this question.