Answer:
D. $100
Explanation:
Given: William install 7 system per day at the cost of $300.
William install 8 system per day at the total cost of $400.
Remember, If the marginal cost curve is upward-sloping, this means that as output increase, marginal costs will also increase.
Marginal cost is an additional cost incurred in producing additional unit of output.
Now, finding additional payment that eighth customer has to pay.
Change in marginal cost= 
⇒ Change in marginal cost= 
∴ Change in marginal cost= 
Hence, there is an increase in marginal cost by $100 as output increases, therefore, William will install eight sound systems per day only if the eighth customer is willing to pay at least $100.
Answer:
A. $66
Explanation:
The price of the company's common stock can be determined by multiplying the industry's price/earning ratio by the earnings per share. If the price/earning ratio is 12, and earnings per share are $5.50, the stock price is:

Therefore, the answer is alternative A. $66.
Answer:
Days of receivable will be 75 days
Explanation:
We have given net credit sales = $1200000
Net account receivable at the beginning = $290000
And receivable at the ending = $201000
Average receivable 
Now receivables turnover ratio 
Days of receivables = 