y = Acos(Bx) + D;
D = 4, A = 2. Now T = 2π/B = 5π/8, B = 2π/(5π/8) = 16/5
WE get y = 2cos(16/5x) + 4
Area=width*height
area=(11.7)*(15.4)
area=180.18cm^2
Answer: 37
Step-by-step explanation:
Given : Significance level : 
Critical value : 
margin of error : E= 1 mile per gallon
Population standard deviation:
miles per gallon.
We know that when the population standard deviation is known then the formula to find the sample size is given by :

[Round to the next whole number.]
Hence, the required number of automobiles should be used in the test = 37
A: the formula would be f(x) = P(R) ^T or f(x) = Principle(rate)^time
B: f(x) = 20,000(0.85)^5
C: = 8,874.10625
D: Yes, the final answer makes sense compared to the origional cost of the car in relation to the formula. As well, time decreases the value of a car, so for the cost to be so low only makes sense due to the cars decrease in value or an extended and elongated amount of time.
E: You can solve this equation graphically by plotting th point at 20,000 and then taking 85% of 20,000 and plotting it each time until you get to the fifth year.
The answer is x=27. your welcome. :)