When the non-dividend paying stock price is $20, the strike price is $20, the risk-free rate is 6%, the volatility is 20% and the time to maturity is 3 months, which of the following is the price of a European call option on the stock?
(Note: N(*) represent cumulative normal density function.)
a. 20*N(0.1) - 19.7*N(0.2)
b. 19.7*N(0.2) - 20N*(0.1)
c. 19.7*N(0.1) - 20N*(0.2)
d. 20N*(0.2) - 19.7N*(0.1)

Self-interest achieve society’s economic goals because producers know which goods consumers want the most. as consumers and producers exercise their freedom to act in their own self-interest, markets will produce the desired goods at the lowest possible cost. consumers and producers both operate based on society’s economic goals. consumers know which goods can be produced at the lowest cost. there is a wide variety of desired goods and services in a market system because producers determine what to produce. consumers change their minds frequently. there is always a need to produce something new and improved. individual wants are diverse. what is produced is ultimately determined by consumers, because if the goods offered are not what consumers want, consumers will not buy them. producers, because they are driven by profits. producers, because they determine what to produce. consumers, because they participate in marketing surveys.

Employees at a library check out books to patrons. books have an isbn and a name. the library sometimes has multiple copies of the same book. books have one or more authors. a patron is an individual who has an active (non-expired) library card. for each library card, we store the person's first and last names and their address. for each employee, we store their employee id, current salary, first and last name and their address. we also store the employee id of their current manager. each time we check out a book to a patron we need to store the date of the transaction, the employee who checked out the book to the patron, and the library card of the patron. some employees have library cards. if an employee patron turns in a book late, the fine that they pay is a percentage of their salary. some employees are authors who have library cards—they are allowed to check out as many books as they like.

On january 1, 2017, sophie's sunlounge owned 4 tanning beds valued at $20,000. during 2017, sophie's bought 3 new beds at a total cost of $14 comma 000, and at the end of the year the market value of all of sophie's beds was $24 comma 000. what was sophie's net investment