Ok. In order to do this set up 2/5 divided by 5/7. The way you divide with fractions is by multiplying them but flipping the second fraction into 7/5 <---this is known as the reciprocal. In other words do:
2/5 x 7/5 =
14/25
There you go.
2.8M/(365x24x60)=wonder why you need this
(4,-1) turns into (1,4) because the equation for that is (x,y)->(y•-1,x)