12. The ratios of the side lengths of a triangle are 7:9:12. The perimeter is 56. What are the lengths of the sides? ​

Fractions can be added and subtracted only if they're fractions. a. like b. proper c. improper d. unlike

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)

Cot(90° − x) = 1 the value of x that satisfies this equation is °. a. 60 b. 135 c. 225 d. 315