Answer:The base of the ladder should be placed so that it is one foot away from the building for every four feet of hight to where the ladder rests against the building. This is known as the 4 to 1 rule.
Step-by-step explanation:

A linear function has 1 as the highest power of the variable.
A. f(x) = 2 - 7x
here, the highest power of the variable x is 1.
Hence it is a LINEAR function.
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B. f(x) = 2 + x + x^2
here, the highest power of the variable x is 2.
Hence it is NOT a linear function.
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here, the highest power of the variable x is 1/2.
Hence it is NOT a linear function.
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Answer:
Im not 100 percent sure but I think you have to do this
Step-by-step explanation:
Add all numbers together to find total students
Then add the students in Chemistry and Physics and both together
Then find what that number is in percent to the total students
1/10 of .9 is the same as dividing .9 by 10.
.90 / 10 = .09
.09 is the answer