What is the greatest common factor gcf gcf of 12 and 18

Find the area of a trapezoid with bases 14 cm and 18 cm and height 10 cm. 160 cm2 140 cm2 180 cm2 126 cm2

Acircular garden with radius of 8 feet is surrounded by a circular path with a width of 3 feet. what is the approximate area of the path alone? use 3.14 for π

We just started the introduction into circles and i have no idea how to do this.