The SI unit for time is seconds (s).
It is the basic unit of time in both systems.
customary
Fahrenheit is a customary unit
it is in the us customary unit or else we wouldnt be learning about. there for it is in the us customary unit.
Seconds
The customary unit of capacity for a bathtub is gallons.
It is a customary unit.
customary
It is a customary unit.
A Customary Unit or non-SI unit is a measurement unit that is not part of the metric system. Customary units are mainly units of the Imperial system but they could be localised customary units - such as Gaj (for area) is South Asia.
The unit of time in both the SI and the "customary" systemsis the second.
The pound is NOT a metric unit.