Recall that

There are three cases to consider:
(1) When

, we have

and

, so

(2) When

and

, we get

and

, so

(3) When

, we have

and

, so

So
Option a:
is the equivalent expression.
Explanation:
The expression is
where 
Let us simplify the expression, to determine which expression is equivalent from the four options.
Multiplying the powers, we get,

Cancelling the like terms, we have,

This equation can also be written as,

Multiplying the terms in denominator, we have,

Thus, the expression which is equivalent to
is 
Hence, Option a is the correct answer.
Answer:
Revenue = 5( 1000 + w+ k)
Step-by-step explanation:
Lets calculate expenses first
rent = $1000
wages = w
overhead cost = k
Total cost = rent + wage+ overhead
Total cost = 1000 + w+ k
Given Jose wants his monthly sales revenue, x, to be 4 times greater than the operating costs
Let revenue be R
Thus, putting the statement mathematically
revenue - total cost = 4 * operating cost
R - ( 1000 + w+ k) = 4( 1000 + w+ k)
R = 4( 1000 + w+ k) + ( 1000 + w+ k)
R = 5( 1000 + w+ k)
Thus, revenue should be 5( 1000 + w+ k).