Find the size of the final unknown exterior angle in a polygon whose other exterior angles are: 57°, 68°, 32°, 59° and 72°.

If a =6, what is the value of 2a(3b + 5c)?

7. the area of the playing surface at the olympic stadium in beijing isof a hectare. what area will it occupy on a plan drawn to a scaleof 1: 500?

The length of a rectangular piece of land is 92 yards more than three times its width. the perimeter is 760 yards. find its dimensions.