College Physics (4th Edition)

$B = 5.4\times 10^{-3}~T$
We can find the magnetic field in the solenoid: $B = \frac{\mu~N~I}{L}$ $B = \frac{(4\pi \times 10^{-7}~T~m/A)(244)(4.5~A)}{0.256~m}$ $B = 5.4\times 10^{-3}~T$