I’m not sure what the rule would be in this context, but those are just the squares of decreasing numbers starting at 10. It’s 10^2, then 9^2, then 8^2, and so on.
4 km/h because 10-2 because of the 2 km left which =8 then you divide that by 2 to figure out the km per hour which = 4 so 4 km/h
I think the interest is 10.60.
And the proceeds are 278.40.
