Tanya has a garden with a trench around it. The garden is a rectangle with length 2 1/2 m and width 2 m. The trench and garden together make a rectangle with length 3 1/2 m and width 3 m. Find the area of just the trench.

If the speed of an electromagnetic wave is 100,000 cm/s and its wavelength is 100 cm, what is its frequency? a) 100,000 cycles per second (hz) b) 1 × 10-3 cycles per second (hz) c) 10,000,000 cycles per second (hz) d) 1,000 cycles per second (hz)