Step-by-step explanation:
1 2/5 miles per hour.
^^
A unit fraction is a fraction where the denominator is one, so the easiest way to write 4/5 as a sum of unit fractions is to use 1/5. So the answer would be 1/5+1/5+1/5+1/5. Add up all the numerators and put that over their like denominators to get 4/5!
Well I guess it should be perpendicular
(140 km/hr) x (1,000 m/km) x (1 hr/3,600sec) = 38-8/9 m/s.