If the antique's value increases over time, it must be growing (not decaying) in value.
We're told the value increases by 12.12%, which means that if the current value is

, then the value after 1 year is

. Each year, the value increases by the same factor, which means after 2 years, the value is

; after 3 years, the value is

; and so on.
Here

is the starting value of the antique. So the answer is the second choice.
Additive inverse means the sum should be 0
so all you gotta do is multiply the complex number by -1
(the question isn't clear so I can't state the option)
Answer is b. A calculator to work out the answer
90x+120 is equivalent to 30 (3x+4)