A magnetic field of 37.2 T has been achieved at the MIT Francis Bitter National Magnetic Laboratory. Find the current needed to achieve such a field
(a) 2.00 cm from a long, straight wire;
(b) At the center of a circular coil of radius 42.0 cm that has 100 turns;
(c) Near the center of a solenoid with radius 2.40 cm, length 32.0 cm, and 40,000 turns.