it depends on about how big it is but i would guess meters or centimeters
You could use meters or feet (or feet and inches), depending on the usage.
I would use feet
You would use meters.
You would answer it with cubic feet
I would use centimetres and millimetres
You would use either inches or centimeters.
centimeter
Inches
cm
You would use a meterstick
You would typically use minutes to measure the length of a television show.