C. $122.10
20 first hour
20+0.1*20 = 22 second hour
22+0.1*22 = 24.2 third hour
24.2+0.1*24.2 = 26.62 fourth hour
26.62+0.1*26.62 = 29.282 fifth hour
Total=$122.10
We have two points describing the diameter of a circumference, these are:

Recall that the equation for the standard form of a circle is:

Where (h,k) is the coordinate of the center of the circle, to find this coordinate, we find the midpoint of the diameter, that is, the midpoint between points A and B.
For this we use the following equation:

Now, we replace and solve:

The center of the circle is (-8,-7), so:

On the other hand, we must find the radius of the circle, remember that the radius of a circle goes from the center of the circumference to a point on its arc, for this we use the following equation:

In this case, we will solve the delta with the center coordinate and the B coordinate.

Therefore, the equation for the standard form of a circle is:

In conclusion, the equation is the following:
<span>the equation that most accurately depicts the word problem
is
3xn=$3.85
proof
n=</span>
<span>n=$3.85/3=$1.28
the price is $1.28 per pound, 3 pound costs 3x$1.28=$3.85
</span>
The equation of line with undefined slope and x - intercept -7 is x = -7
<em><u>Solution:</u></em>
Given that the slope of line is undefined and the x intercept is -7
To find: Equation of line
If a line has undefined slope, then it is a vertical line
A vertical line has undefined slope because all points on the line have the same x-coordinate
<em><u>The equation of a vertical line always takes the form:</u></em>
x = b
where, "b" is the x - intercept
Given x - intercept is -7
<em><u>Thus the equation of line is:</u></em>

Therefore, the equation of line is found