Answer: Option A is correct.
Step-by-step explanation:
- The correlation coefficient(r) is a statistical measure that computes the strength of the relationship between two variables.
It lies between -1 and 1.
If the correlation coefficient in an ordinary least squares regression = 1.00.
That indicates that there is a perfect relationship between the variables.
i.e. all the data points must fall exactly on a straight line with a positive slope. .
[when r is positive, the slope of the line is positive].
i.e. option A is correct.
You have to pay a certain amount each month
Answer:
r = 144 units
Step-by-step explanation:
The given curve corresponds to a parametric function in which the Cartesian coordinates are written in terms of a parameter "t". In that sense, any change in x can also change in y owing to this direct relationship with "t". To find the length of the curve is useful the following expression;

In agreement with the given data from the exercise, the length of the curve is found in between two points, namely 0 < t < 16. In that case a=0 and b=16. The concept of the integral involves the sum of different areas at between the interval points, although this technique is powerful, it would be more convenient to use the integral notation written above.
Substituting the terms of the equation and the derivative of r´, as follows,

Doing the operations inside of the brackets the derivatives are:
1 ) 
2) 
Entering these values of the integral is

It is possible to factorize the quadratic function and the integral can reduced as,

Thus, evaluate from 0 to 16
The value is 
Answer:
$803.25
Step-by-step explanation:
Given data
Dimension for the room
Length= 21 ft
Width= 17ft
Area= L*W
Area= 21*17
Area= 357 ft^2
Lucy will need to get 357ft^2 of carpet
We are given that a square ft cost $2.25
Hence to carpet the room the cost will be $2.25*357= $803.25