Geology, please help!!?
(Q003) Part 3.a. Evidence shows that there were once Himalayan-scale mountains in northern Canada, in an area now eroded nearly flat. If the Earth were only 6,000 years old, as was once believed, how fast would the rate of erosion have had to be for these mountains to be eroded to sea level in 6,000 years? Give your answer in meters and millimeters.
a. 682 m/yr; 682,000 mm/yr
b. 0.682 m/yr; 681 mm/yr
c. 1.47 m/yr; 1,470 mm/yr
d. 0.00147 m/yr; 1.47 mm/yr