Harper and Dean raced each other in gym class. Harper ran 100 m in 14.56 seconds. Dean ran the same distance in 15.12 seconds. How much faster was Harper than Dean?

I'll give brainliest if you answer right : )

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)

For what values of x is x2 + 2x = 24 true?