Given a scientific passage and an answer, generate a question for the given answer.

Passage: Loudness refers to how loud or soft a sound seems to a listener. The loudness of sound is determined, in turn, by the intensity, or amount of energy, in sound waves. The unit of intensity is the decibel (dB). Answer: decibel
What is the term used to measure the intensity of sound waves?

Passage: Christopher Auyeung, using bat image by User:Rugby471/Wikimedia Commons. Bats use echolocation to identify the location of objects . CC BY-NC 3.0 (bat image available under public domain). Answer: echolocation
What do bats use to determine the location of objects?

Passage: Unlike nonvascular plants, all vascular plantsincluding seedless vascular plantshave a dominant sporophyte generation. Seedless vascular plants include clubmosses and ferns. Figure below shows a typical fern life cycle. Answer: vascular
Do nonvascular or vascular plants have a dominant sporophyte generation?