In this task, you are given a question and a context passage. You have to answer the question based on the given passage.

[Q]: Who helped prepare?, Context: The Apollo astronauts were chosen from the Project Mercury and Gemini veterans, plus from two later astronaut groups. All missions were commanded by Gemini or Mercury veterans. Crews on all development flights (except the Earth orbit CSM development flights) through the first two landings on Apollo 11 and Apollo 12, included at least two (sometimes three) Gemini veterans. Dr. Harrison Schmitt, a geologist, was the first NASA scientist astronaut to fly in space, and landed on the Moon on the last mission, Apollo 17. Schmitt participated in the lunar geology training of all of the Apollo landing crews.
[A]: Schmitt

[Q]: How are the tasks of a freemason dictated?, Context: During the ceremony of initiation, the candidate is expected to swear (usually on a volume of sacred text appropriate to his personal religious faith) to fulfil certain obligations as a Mason. In the course of three degrees, new masons will promise to keep the secrets of their degree from lower degrees and outsiders, and to support a fellow Mason in distress (as far as practicality and the law permit). There is instruction as to the duties of a Freemason, but on the whole, Freemasons are left to explore the craft in the manner they find most satisfying. Some will further explore the ritual and symbolism of the craft, others will focus their involvement on the social side of the Lodge, while still others will concentrate on the charitable functions of the lodge.
[A]: There is instruction as to the duties of a Freemason, but on the whole, Freemasons are left to explore the craft in the manner they find most satisfying

[Q]: What temp is the hydrogen purified by?, Context: Hydrogen is highly soluble in many rare earth and transition metals and is soluble in both nanocrystalline and amorphous metals. Hydrogen solubility in metals is influenced by local distortions or impurities in the crystal lattice. These properties may be useful when hydrogen is purified by passage through hot palladium disks, but the gas's high solubility is a metallurgical problem, contributing to the embrittlement of many metals, complicating the design of pipelines and storage tanks.
[A]:
hydrogen is purified by passage through hot