4. Ship's power is generated as 3-phase and is ungrounded. On a delta-wound transformer with 120 VAC line-to-line secondary, what is the voltmeter reading from line to ground:

In an ungrounded 3-phase delta system, the line-to-ground voltage varies depending on system conditions. It can be approximately 67 volts in a balanced system, 0 volts if a phase is faulted to ground, or 120 volts if another phase is faulted to ground; therefore, any of these readings are possible.