Final answer:
The maximum square footage for the one-story building is calculated by subtracting the required setbacks from the lot's dimensions. After adjustments for the setbacks, the lot dimensions are 70 feet by 90 feet, yielding a maximum buildable area of 6,300 square feet.
Step-by-step explanation:
To determine the maximum square footage of a one-story building that can be built on a lot measuring 110 feet wide by 140 feet deep with required setbacks, we need to subtract the setbacks from each side of the lot.
The front setback is 30 feet, the rear setback is 20 feet, and there are 20 feet setbacks on each side. Thus, the buildable width is 110 feet - 20 feet - 20 feet = 70 feet, and the buildable depth is 140 feet - 30 feet - 20 feet = 90 feet.
Now, we can calculate the maximum buildable area by multiplying the buildable width and buildable depth: 70 feet × 90 feet = 6,300 square feet. Therefore, the correct answer is c. 6,300 sq ft.