An ideal toroidal solenoid (see Example 28.10) has inner radius r1 = 15.0 cm and outer r...

An ideal toroidal solenoid (see Example 28.10) has inner radius r₁ = 15.0 cm and outer radius r₂ = 18.0 cm. The solenoid has 250 turns and carries a current of 8.50 A. What is the magnitude of the magnetic field at the following distances from the center of the torus: (a) 12.0 cm; (b) 16.0 cm; (c) 20.0 cm?