A and b are both accurate
For a:

which is true
For b:

which is also true
$12.6 -- 25% of 12.6 is exactly $3.15
I did this by taking 3.15 / 0.25
Answer:
$8511.11
Step-by-step explanation:
Each year, the amount Walter owes is multiplied by 1.06, so at the end of 6 years, Walter owes 1.06^6 times the amount he borrowed.
he will pay $6,000×1.06^6 ≈ $8511.11
_____
At the end of the first year, Walter owes the original loan amount plus 6% interest. That total is ...
$6000 + 0.06×6000 = $6000×1.06
At the end of the following year, he owes 1.06 times that amount, or ...
6000×1.06²
The amount owed is multiplied by 1.06 each year until Walter pays off the loan.
ANSWER
"If x=7, then x - 2 = 5"
EXPLANATION
Let

be a propositional statement.
The converse of this statement is

In other words, the converse of the statement,
"If p then q" is "If q, then p"
The given given conditional statement is
"If x - 2 = 5, then x = 7"
Therefore the converse is
"If x=7, then x - 2 = 5"
Exact Surface Area = 378pi
Approximate Surface Area = 1186.92
The approximate surface area uses pi = 3.14
The units are cm^2 or "square cm".
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Work Shown:
SA = surface area of cylinder
SA = 2*pi*r^2 + 2*pi*r*h
SA = 2*pi*7^2 + 2*pi*7*20
SA = 2*pi*49 + 2*pi*140
SA = 2*49*pi + 2*140*pi
SA = 98pi + 280pi
SA = 378pi ..... exact surface area
SA = 378*3.14
SA = 1186.92 ..... approximate surface area
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Side note: The diameter 14 cuts in half to get the radius r = 7