Which of the following quotations illustrates the tragedy of the commons?
a. "a bird in the hand is worth two in the bush."
b. "the only difference between the rich and other people is that the rich have more money."
c. "what is common to many is taken least care of, for all men have greater regard for what is their own than for what they possess in common with others."
d. "anyone who is not a socialist before he is 30 has no heart; anyone who is still a socialist after he is 30 has no head."

The correct answer is option c.

Explanation:

The tragedy of the commons is an economic problem in which individuals' rational decisions lead to collective irrationality. The individual consumers want to maximize their satisfaction so they consume a common resource in the way to maximize utility or satisfaction. But collective consumption in this manner leads to overconsumption of resources.  

Individuals take better care of the resources they privately own than the common resources. Individuals focus on their wellbeing instead of the collective welfare of society and ignore social welfare in the process of maximizing their personal welfare.

40000 units were produced during the period

Explanation:

Depreciation and amortization are not included in the cost of goods sold and are expensed as separate line items on the income statement.

To calculate the total cost of units we need to sum:

$30,000 for direct materials

$50,000 in wages for production workers

$20,000 selling and administrative expenses

Total cost= $100000

Cost per unit= Total cost/Qunits

Q=Total cost/cost per unit

Q=100000/2,5=40000units