Correct the four pronoun-related errors in this paragraph: Fast-forwarding to modern times, the heyday of the human-powered flight is far from over. Lucrative prizes still abound for rotor-driven craft,
whilst experimental versions of helicopters and ornithopters (flying machines with flapping, bird-like wings) are both on the drawing board
and leaping off it with great abandon. The dream of human-powered flight has been an official reality now for more than 50 years, but the
limits of their ingenuity are boundless - especially when inventors and engineers are spurred on by prizes as large as the $250,000 on offer
from the American Helicopter Society's Igor Sikorsky Prize Fund. And who knows, perhaps one day his commute to work will take place not on
a bicycle but on a bicycle-powered craft. Does your office have a landing pad on the roof or a runway nearby? The day when she does might
just be closer than we think!

Correct the four pronoun- related errors in this paragraph

we both have laws and checks and balances.

marginal cost is a microeconomic measure that us to evaluate the extent to which the level of production of a good is sustainable in accounting, that is, to how many quantities the company plans to profit from the production of the good.

the concept of marginal cost is simple, it means the cost of producing one more item. for example, in the case of pies, the marginal cost is the cost of producing one more pie than those that have already been produced.

it is important to understand that productive activity influences marginal cost. the marginal cost of some goods can be very high, while others may be insignificant. for example, the marginal cost of producing an extra plane is very high. already the marginal cost of a water company to provide 1l more water is derisory.

in the case of pies, the cost involves the inputs, the labor and the fixed cost, which involves the fixed space of the bakery. the level of production initially has the marginal cost decreasing because there is space and manpower available. however, to produce more you have to hire more workers and buy more inputs. if physical space is limited, workers will conflict with places, inputs and their productivity will decrease, meaning there is an optimum point of production for each level of space and manpower. from this point on, the productivity of the workers will be getting smaller because of lack of space, so that the marginal cost of producing one more pie will be increasing. so, although you have not posted the chart, but if you have the answer, you can see that my explanation goes according to the marginal cost curve that will increase from the 4th pie, answer (c).

the answer is d.index

answer; cindy crawford tina feycarrie underwood///meryl streep;