Answer:
D) 191
Step-by-step explanation:
The entire circle is 254.5, calculated by using this formula

Only 3/4 of the circle is needed for the area, however, so you multiply your area by 0.75
An ecosystem is a community of living organisms in conjunction with the nonliving components of their environment, interacting as a system. These biotic and abiotic components are linked together through nutrient cycles and energy flows. ... Ecosystems are controlled by external and internal factors.

the first step is to deal with the negative exponents, which causes numbers to go to the other side of the fraction
8x^{-9}+(-3x^{-3}y^{-2})(\frac{5}{x^6y^{-2}})
goes to

now we can simplify the multiplied terms

Now that we have common bases, we can add the 2 fractions together to get

Answer:
idk this stuff yet
Step-by-step explanation: