The total fixed cost curve is

Step 1: Analyze the question We are asked about the shape of the Total Fixed Cost (TFC) curve when it is plotted on a graph. Output is on the horizontal axis and cost is on the vertical axis.

Step 2: Explain the concept Fixed costs are costs that do not change with the level of output. Examples are rent, insurance, and salaries of permanent staff. Whether a firm produces 0 units or 10,000 units, the total fixed cost stays the same in the short run.

Step 3: Work through the solution Suppose a bakery in Ibadan pays ₦50,000 rent every month:

| Output (loaves) | TFC (₦) | |---|---| | 0 | 50,000 | | 100 | 50,000 | | 500 | 50,000 | | 1,000 | 50,000 |

TFC has the same value at every output level. When you plot a constant value against output, you get a straight line parallel to the horizontal (output) axis.

Step 4: Check the other options

• Upward sloping: this is the shape of Total Variable Cost (TVC) and Total Cost (TC), which rise as output rises.
• Vertical: this would mean output stays fixed while cost changes, which does not describe fixed cost.
• Downward sloping: this is the shape of Average Fixed Cost (AFC), because the same fixed cost is spread over more units.

Answer: A. Horizontal

Exam tip: Remember "Fixed = Flat." Total Fixed Cost is a flat (horizontal) line. Average Fixed Cost slopes downward, and Total Variable Cost slopes upward. WAEC often tests the difference between TFC and AFC.