Answer:
4/9
Step-by-step explanation:
Given rate is 1/3 acre per 3/4 hours.
To calculate the rate per hour, we have to divide total acres by the fraction of hour
=> 
=> 
=> 4/9
we are given to find

we know that

where
i is number of rows
j is number of column
Here , we get
i=2
and j=3
so,
means second row and third column
we can look at matrix and find element
we can see that
that element is -21
so,
...........Answer
I am prerty sure it is 1/3 because 5 is 1/3 of 15 and 15 is 1/3 of 45