A botany student counted 11 blades of grass in one square centimeter of

lawn and measured the lawn as a rectangle 61 m by 31 m. She reported
that there were 208,010,000 blades of grass in the lawn. The precision
of her conclusion:
A. correctly represents her measurements.
B. is less than her measurements warrant.
C. could be greater if she used a more precise calculator.
D. is excessive given her measurements

Answer: D

To determine the precision of the conclusion reached by the botany student, we need to compare the precision of her measurements (11 blades of grass in one square centimeter) with the precision of her reported result (208,010,000 blades of grass in the entire lawn).

First, let's calculate the total area of the lawn to find the total number of square centimeters:
Area = Length × Width = 61 m × 31 m = 1891 square meters

Since 1 square meter is equal to 10,000 square centimeters, the total area of the lawn in square centimeters is:
1891 m^2 × 10,000 cm^2/m^2 = 18,910,000 cm^2

Now, we can estimate the total number of grass blades by multiplying the total area of the lawn by the number of grass blades per square centimeter:
Total number of grass blades = 18,910,000 cm^2 × 11 blades/cm^2 = 208,010,000 blades

Comparing this result to the reported result of 208,010,000 blades, we can see that they are exactly the same. This means the precision of the botany student's conclusion matches her measurements exactly.

Therefore, the correct answer is D. The precision of her conclusion is excessive given her measurements, as there is no rounding or estimation involved.