Answer: C
Step-by-step explanation:
The decomposition of the parallelogram into triangle then into a rectangle is shown below
The measurement we need to calculate the area is the length and the width of the rectangle; 15 feet and 10 feet
Area = 15 × 10 = 150 feet²
The effective rate is calculated in the following way:

where r is the effective annual rate, i the interest rate, and n the number of compounding periods per year (for example, 12 for monthly compounding).
our compounding period is 2 since the bank pays us semiannually(two times per year) and our interest rate is 8%
so lets plug in numbers:
The answer is false, it is only true for postulates, not conjectures.