An exponent is a number written above and to the right side of a value or number in math. The value or number is called the base, and the expression is read out as;
"Base raised to the power of exponent."
An example is given below;

In this example, 10 is the base and 3 is the EXPONENT.
The expression is now read out as,
"10 raised to the power of 3"
Note that even unknown values (such x as we commonly use in math) can also be an exponent or base. For example, we can have;

So basically, an exponent indicates the number of times a number is used to multiply itself.
I think its c.
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Answer:

Step-by-step explanation:
-5+2(10b-2)=31
Expand brackets.
-5+20b-4=31
-9+20b=31
Add 9 on both sides.
20b=40
Divide both sides by 20
b=2
Answer:
Step-by-step explanation: 45% based on the way you state the question. 45% is a whole percent.
The answer is the triangles could have the same shape( that is all the angles are equal) but the sides may not be the same length . Thay are similar but not necessarily congruent.
C is the correct choice.