Final answer:
The average body thickness of a dinosaur with a hip-to-shoulder length of 9 feet can be calculated using the given power law equation.
Step-by-step explanation:
The study of size and shape, known as allometry, often involves relationships with fractional exponents. In the case of the given example, the average body thickness of most four-legged animals can be estimated using the power law equation: Average body thickness = 0.4 * (hip-to-shoulder length)^(3/2). To find the average body thickness of a dinosaur with a hip-to-shoulder length of 9 feet, we can substitute this value into the equation.
Average body thickness = 0.4 * (9 feet)^(3/2)
Using a calculator, we can evaluate this expression and find that the average body thickness of the dinosaur is 7.2 feet. Therefore, the correct answer is d) 7.2 feet.