Solve the Problem $$14 \mathrm { in } .$$ A Use a Coordinate System with the Origin at the Mirror

Multiple Choice

Solve the problem.
-Suppose a solar cooker has a parabolic mirror (see figure) .
$$14 \mathrm { in } .$$ a. Use a coordinate system with the origin at the vertex of the mirror and write an equation of a parabolic cross section of the mirror.
b. Where should a pot be placed so it receives maximum heat?

A) a. $x ^ { 2 } = 14 y$ for $- 14 \leq x \leq 14$
b. The pot should be placed $3.5 \mathrm { in }$ . above the vertex
B) a. $x ^ { 2 } = 28 y$ for $- 14 \leq x \leq 14$
b. The pot should be placed 28 in. above the vertex
C) a. $x ^ { 2 } = 14 y$ for $- 14 \leq x \leq 14$
b. The pot should be placed $14 \mathrm { in }$ . above the vertex
D) a. $x ^ { 2 } = 28 y$ for $- 14 \leq x \leq 14$
b. The pot should be placed 7 in. above the vertex