The Resistance $y$ In Ohms of 1000 Feet of Solid Metal Wire At Metal

Multiple Choice

The resistance $y$ in ohms of 1000 feet of solid metal wire at $77$ $F^{\circ}$ can be approximated by the model $y = \frac { 12,750 } { x ^ { 2 } } - 0.37,5 \leq x \leq 100$ , where $x$ is the diameter of the wire in mils $( 0.001$ in $)$ . If the diameter of the wire is doubled, the resistance is changed by approximately what factor? In determining your answer, you can ignore the constant $- 0.37$ .

A) 3
B) $\frac { 1 } { 2 }$
C) 4
D) $\frac { 1 } { 4 }$
E) $\frac { 1 } { 3 }$