Answer:

243 m

Step-by-step explanation:

The volume of the sphere and the cylinder (wire) will be equal.

Let the height of the cylinder, which is the length of the wire, be x.

Thus,

π × [ ( 4 / 10 ) / 2 ] ^2 × x = ( 4 / 3 ) × π × 9 ^3

(4 / 20 ) ^2 × x = ( 4 / 3 ) × 729

( 1 / 5 ) ^2 × x = 4 × 243

( 1 / 25 ) × x = 972

x = 24300 cm = 243 m