C in my opinion
#CarryOnLearning
Find the scale between sides xz and gh
18/4 = 4.5
Multiply the length of fh by the scale to find x
6 x 4.5 = 27
x = 27
Answer: 68
Step-by-step explanation:
As per given , we have
Population standard deviation : 
Critical value for 90% confidence interval =
Margin of error : E= 0.8 milligrams
The formula to find the sample size is given by :-

i.e. 

Hence, the limnologist must analyze 68 samples.
Answer:
0 ≤ c ≤ 12
Step-by-step explanation:
The function can be rearranged to ...
p = 200c(12 -c) -4700
suggesting that revenue will be zero for a charge of 0 or for a charge of 12, and that fixed expenses are 4700. Charges less than 0 are uninteresting, and charges high enough to cause the number of customers to be negative also don't make any sense in this context.
Though out of the range of likely consideration, charges low or high enough to cause profit to be negative (more than 9.54, for example) seemingly can be reasonably modeled by this function.