The presence of _______________ increases the possibility that a human lunar base may be established someday.
Fill in the blank(s) with correct word
Question 2
A massive star can fuse more and more massive nuclei, but this process is limited by the fact that, at some point, an element that is produced ____.
a. becomes completely degenerate in the core, changing the pressure-temperature relationship
b. cannot produce energy through fusion
c. will only fuse in the presence of even more massive nuclei
d. is not found in nature
e. decays radioactively before it can undergo fusion
