Hello :
the normal vector of the plane is : d' = [4,-1,5]...(vector perpendicular to the plane)<span>
d </span><span>⊥ d' because : (4)(2)+(-1)(3)+(5)(1)=0
</span>the line is perpendicular to the plane .
Your answer is C. Hope this help :D
It equals 18.32 you can go to calculatorsoup.com and it shows you
It would be B (530.7) because if you do 3.14 x 13 x 13 (Or to the second power) Then you get 530.66, the round to the nearest tenths
Each year the boat is worth 100-12 = 88% ( or 0.88) of the year before
after 12 years the boat is worth 12050 * 0.88^9 = $3813.56