Jessica is selling books during the summer to earn money for college. She earns a commission on each sale but has to pay for her own expenses.
After a month of driving from neighborhood to neighborhood and walking
door-to-door, she figures out that her weekly earnings are approximately a
linear function of the number of doors she knocks on.
She writes the equation of the function like this: E(x) = 10x - 30, where x is the
number of doors she knocks on during the week and E(x) is her earnings for
the week in dollars.
Which of the following are reasonable interpretations of the y-intercept of
Jessica's function?

Check all that apply:
A.) If she does not knock on any doors at all during the week, she will lose $30
B.) She can earn $10 per week even if she does not knock on any doors
C.) She will lose $10 per week if she does not knock on any doors
D.) Her expenses are $30 per week