How are elements usually found?
in their pure state by themselves.
in compounds with other elements.
as individual atoms in gas clouds.
in mixtures with other elements.

I think your answer would be D. In mixtures with other elements.

dear friend:

  i hope this letter finds you in soaring spirits and vibrant health. as you had expressed the wish to know about culture, traditions, and unity of india in your previous letter, in the following lines i have tried my best to give you glimpses of our culture, traditions, and unity. you will be amazed to know that our culture is the oldest culture in the world and the birth place of hinduism, buddhism, jainism, and sikhism. you won’t find any other culture as varied and multi-colored, multi-lingual as ours. each region has its own unique culture, traditions, language. there are 22 official languages in india.

  basically, india is a spiritual country with orthodox traditions. for example the people of india believe in traditions set by their wise forefathers. arranged marriages, joint-family system, universal brotherhood, vegetarianism, celebrating festivals such as diwali, holi, eid, etc., are the salient features of our culture and traditions.

  another unique aspect about our country is ‘unity in diversity’. in spite of the multi-lingual, multi-religious, multi-traditional, multi-cultural society, people live peacefully together, respecting one another’s views, cultures, traditions, and differences. i am sure you would love to visit india soon, and have a first-hand experience of the multi-colored culture. give regards to uncle and aunt. do visit india with your family and experience our hospitality.

your friend,

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).