Find the area of a circle given the diameter of 12

Find the sum of the measure of the interior angles of a polygon of 9 sides ; of 32 sides

Can someone me with this problem i don't understand i need

Gregory draws a scale drawing of his room. the scale that he uses is 1 cm : 4 ft. on his drawing, the room is 3 centimeters long. which equation can be used to find the actual length of gregory's room?