Step-by-step explanation:
We have 8 + 12 + x = 29.
Solving, we get x + 20 = 29, x = 9.
$1.50 for each box
Step-by-step explanation:
$18 divided by 12 boxes = $1.50 for each box
Let z=x+iy be a complex number. The distance from this complex number to the origin is

Consider all options:
A. z=2+15i, then 
B. z=17+i, then 
C. z=20-3i, then 
D. z=4-i, then 
Answer: correct choice is D.