Answer:
C. The sum of 18 and half the product of 9 and 4.
The first choice if ()2 means to the power of two if not then it is none of them.
Answer:

Variable is a symbol that represents a quantity in a mathematical expression, as used in many sciences. Variable (research), a logical set of attributes. Variable star, a type of astronomical star.

A constant, sometimes also called a "mathematical constant," is any well-defined real number which is significantly interesting in some way. A function, equation, etc., is said to "be constant" (or be a constant function) if it always assumes the same value independent of how its parameters are varied.
Answer:
It is A [1st option]
Step-by-step explanation:
Use process of elimination.
The last 2 would not work since 3^0 is 1 not 0.
Then you can eliminate the 2nd option as it says 2^3^2 is 2^5 which is wrong... it would be 2^6
Therefore, it is A
I can't explain it with words so here's the equation, hopefully you understand:
875/125=7