Step-by-step explanation:

The problem here is: Too many words.
If you boil the problem down to the bare facts, the question is:
"$210 is 15% of what number ?"
I'm pretty sure you can take it from there,
but here's the rest of it anyway:
$210 = 15% of (March amount)
$210 = 0.15 x (March amount)
Divide each side by 0.15 : $1400 = March amount .
Check:
1400 + 210 = 1610
1.15 x 1400 = 1610 yay!
Sub (x+1) for x
f(x+1)=2(x+1)^2+3
f(x+1)=2(x^2+2x+1)+3
f(x+1)=2x^2+4x+2+3
f(x+1)=2x^2+4x+5
D is answer
There are 2² butterflies.
Or simply 2²
The sales tax rate is 6.5%