Sorry i forgot to upload the attachment with it i need help with this

Mary used 1/7 of a spool of ribbon to complete 4 projects. she used the same amount of ribbon on each project. how much ribbon did she use on each project?

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)

41/17 as a decimal rounded to the nearest hundredth