Answer:
i think you can divide 2,000 and 30 it might get you the answers if not try these adding multiplucation or subtraction.
Answer:

f(x) = 4 when x is 8
Step-by-step explanation:
Domain is the set of x values that make the function defined. Allowed x values for the function (mapping).
The Range is the set of y values that make the function defined. Allowed y values for the function (mapping).
- Whenever we need to find f(a), suppose, then we look for "a" in the domain and see its corresponding value mapping in the range.
- Whenever we will be given a value for f(x) = a, suppose, and we have to find "x", we look at the value a in the range and find corresponding x value in the domain.
Firstly, we need f(4), so we look for "4" in domain and see which number it corresponds to in range.
That is 
Thus,

Next,
We want "x" value that gives us a "y" value of 4. We look for "4" in the range and see which value it corresponds to. That is "8". So,
f(8) = 4
In order to get the total price, we can multiply the 4 dollars by .05 to find 5 percent of the object's cost and add it to the sales tax. So, .05 times 4 is 0.2, meaning there is a sales tax of 0.2 dollars. We add that to the four, so the total price is 4.20 dollars. Hope this helps.
B. The total area painted is 864; they must buy two cans of paint.
Step-by-step explanation:
Step 1:
A rectangle's area can be calculated by multiplying its length and its width. The wall is made up of 5 different types of rectangular walls. All walls are 8 feet tall but the length varies.
Step 2:
The area of the 20 feet long wall = 
The area of the 10 feet long wall = 
The area of the 5 feet long wall = 
The area of the 4 feet long wall = 
The area of the 15 feet long wall = 
The area of all the walls = 432 square feet.
Since there are two sides for every wall, total area =
square feet.
Step 3:
If one paint can covers 500 square feet,
the number of cans required to paint 864 square feet =
cans.
so 2 paint cans are needed to paint 864 square feet which is option B.