A company finds that there is a linear relationship between the amount of money that it spends on advertising and the number of units it sells. If it spends no money on advertising it sells 150 units. For each additional $2500 spent, an additional 25 units are sold.

a) If $x$ is the amount of money that the company spends on advertising, find a formula for $y$, the number of units sold as a function of $x$. (Do not use commas in your formula.)
$y = \ $

b) How many units does the firm sell if it spends $25,000 on advertising? (Do not include any commas in your answer.)
units

c) How many units does the firm sell if it spends $50,000 on advertising? (Do not include any commas in your answer.)
units

d) How much advertising money must be spent to sell 700 units? (Do not include any commas in your answer.)
$

e) Which of the following statements CORRECTLY explains the meaning of the slope? (select all as there may be more than one correct statment)

A. If the company increases the amount of money it spends on advertising by $150, it will double the number of units it sells.
B. If the company spends an additional $1000 on advertising, it will increases the number of units it sells by 10 .
C. In order to sell one more unit, the company would need to increase the amount it spends on advertising by $100 .
D. If the company spends an additional $0.01 on advertising, it will sell one more additional unit.
E. None of the above