Answer:
I am 99.99% sure it is the first one
If mark and 8 of his friends went out the total of people is 9, so if you think about it 9x9=81 so the total cost of the bill was $81
Answer:
B, E
Step-by-step explanation:
The equation of that line in slope intercept form is y = -2/5x + 2
The slope of a line parallel to that line will be the same as its slope, so -2/5.
To find the y-intercept of a line that passes through the point (-5, 1) with that slope, you will have to plug in the x and y values of that point into what you know of the equation of the line.
y = -2/5x + b
1 = -2/5(-5) + b
1 = 2 + b
-1 = b
From this, you can construct an equation.
y = -2/5x - 1
However, this is not an answer choice.
It cannot be A because this line does not have a slope of -1.
2x + 5y = 15
5y = -2x - 5
y = -2/5x - 1
It can be B because this line is the same as the equation we came up with.
It cannot be C because this line does not have a slope of -1 or a y-intercept of -3.
2x + 5y = -15
5y = -2x - 15
y = -2/5x - 3
It cannot be D because this line does not have a y-intercept of -3.
y - 1 = -2/5(x + 5)
y - 1 = -2/5x - 2
y = -2/5x - 1
It can be E because this equation matches the one we came up with.
The frequency of the emitted radio waves is:
The energy of a photon is given by:
where h is the Planck constant and f is the photon frequency. Using the frequency given by the problem, we can find the energy of each photon of this radiation:
