<span>First of all, there should be coherence for the units of measurement -- either they are all meters or they are all ft. I would assume they are all ft.
The correct answer is 75 ft above. T
The explanation is the following: suppose the ground level is the x-axis, the 2 feet of the arch lie respectively on (0,0) and (100,0) on the ground level. Since the arch is 100ft high, the vertex of the parabola will be the point (100,100). Thus, we can find the equation describing the parabola by putting the three points we know in a system and we find that the equation of the parabola is y=(-1/100)x^2+2
To find the focus F, we apply the formula for the focus of a vertical axis parabola, i.e. F(-b/2a;(1-b^2+4ac)/4a).
By substituting a=-1/100, b=2 and c=0 into the formula, we find that the coordinates of the focus F are (100,75).
So we conclude that the focus lies 75ft above ground.</span>
Answer: c. sampling error
Step-by-step explanation:
- A population parameter is a number that is evaluated to describe the whole population . For example : Population mean , Population standard deviation etc.
- A sample statistic gives the estimate value of the population parameter. For example : Sample mean , sample proportion.
Since, the sample is a subset of population , so there are chances for unavoidable variation in sample mean from the population mean that varies from sample to sample .
This variation is known as sampling error.
∴ The difference between the value of the sample statistic and the value of the corresponding population parameter is called the sampling error .
Hence,the correct answer is c. sampling error .
Answer:
81
Step-by-step explanation:
[character limit thing]
Answer:
The histogram of the sample incomes will follow the normal curve.
Step-by-step explanation:
According to the Central Limit Theorem if we have an unknown population with mean <em>μ</em> and standard deviation <em>σ</em> and appropriately huge random samples (<em>n</em> > 30) are selected from the population with replacement, then the distribution of the sample mean will be approximately normally distributed.
In this case the researches wants to determine the monthly gross incomes of drivers for a ride sharing company.
He selects a sample of <em>n</em> = 200 drivers and ask them their monthly salary.
As the sample selected is quite large, i.e. <em>n</em> = 200 > 30, the central limit theorem can be applied to approximate the sampling distribution of sample mean by the Normal distribution.
Thus, the histogram of the sample incomes will follow the normal curve.
Answer:
x= (-2, 0) y=(0, -5)
Step-by-step explanation:
or you could say -2 and -5
