Answer:
Sandwich sells for $4.76 .
Step-by-step explanation:
As given
It costs $2.80 to make a sandwich at the local deli shop.
To make a profit, the deli sells it at a price that is 170% of the cost.
170% is written in the decimal form

= 1.7
Thus
Sandwich selling cost = 1.7 × Cost of making
Put all the values in the above
Sandwich selling cost = 1.7 × $ 2.80
= $4.76
Therefore the Sandwich sells for $4.76 .
If you evaluate directly this function at x=0, you'll see that you have a zero denominator.
Nevertheless, the only way for a fraction to equal zero is to have a zero numerator, i.e.

So, this function can't have zeroes, because the only point that would annihilate the numerator would annihilate the denominator as well.
Moreover, we have

So, we can't even extend with continuity this function in such a way that 
9514 1404 393
Answer:
1367 people
Step-by-step explanation:
The wording "a rate proportional to the number" indicates the function is exponential. The growth factor is 1200/1000 = 1.2 in 7 days, so the exponential function can be written ...
i(t) = 1000(1.2^(t/7))
After 12 days, the number infected is modeled as ...
i(12) = 1000(1.2^(12/7)) ≈ 1367
About 1367 people are infected 12 days after discovery.
To find the unit rate you divide 12 by 5.79 to get the estimate of 2. Answer is 2.