What is the unit rate for 64 books on 4 shelves

Whats the name of the vertical axis

Write the equations in logarithmic form 10^3=1,000

Two farmers pay a total rent of $140 for a pasture. the first farmer placed $4 oxen in the pasture, and the second farmer placed $30 sheep in the pasture. the farmers split the rent based on the proportion of the pasture eaten by their own animals that month. how much should the first farmer pay, if 1 ox eats as much as 10 sheep in a month?