Answer:
The error is at step (3) .
The correct step (3) will be,

=
[by using the laws of indices]
All other steps are correct.
Step-by-step explanation:
The error is at the step (3) , because the student has tried to prove the quotient rule of logarithms by using the property i.e., 'The quotient rule of logarithm' itself , i.e. ,by assuming the property does hold before proving it. So, the proof is fallacious.
The correct step (3) will be,

=
[by using the laws of indices]
All other steps are correct.
Answer:
the answer is 15 I'm positive
The building is about 70.95 feet tall.
The building and the laser range will form a right triangle. You can use the Pythagorean Theorem to find the height of the building.
112^2 + b^2 = 131^2
b = 67.95
However, don't forget to add on 3 because that is the height of the laser range.
For a more see orthocenter of a triangle .The orthocenter is the point where all three altitude of the triangle intersect. An altitude is a line which passes through a vertex of the triangle and is a perpendicular to the opposite side. Hope this helps :)
We first must find the difference between the two prices. So let's subtract:

Now we take this difference and divide it by the original amount that the price was:

This is the decimal form of the answer. In order to make it a percent, we must multiply it by 100:

So the percent change in this price is 9%.