Can someone answer this! (1/4 + 5/4)^2 +3/4

When i add money am i supposed to make it like this 7+12 or 7.00+12.00 because i got 19 dollars for my answer

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)

3.4a=57.8 what is the the value of a