TASK DEFINITION: Given scientific fact as input, generate the question from this fact such that it can be answered from the input.
PROBLEM: The nuclear envelope is a double-layered plasma membrane like the cell membrane, although without membrane proteins.

SOLUTION: The nuclear envelope is a double-layered plasma membrane like the cell membrane, although without what?

PROBLEM: Ultrasound, a diagnostic technology, uses high-frequency vibrations transmitted into any tissue in contact with the transducer.

SOLUTION: What diagnostic technology uses high-frequency vibrations transmitted into any tissue in contact with the transducer?

PROBLEM: Most molecular compounds that have a mass similar to water are in gas state of matter at room temperature.

SOLUTION:
Most molecular compounds that have a mass similar to water are in what state of matter at room temperature?