Why was the Martian meteorite ALH84001 singled out for intense study?
A) it is the only Martian meteorite that has even been discovered
B) the meteorite appeared to be giving off methane gas
C) it is a very young rock originating from the Tharsis region
D) it is a very old rock, dating back from the time when Mars probably had liquid water on its surface
Question 2
In the process of nuclear fusion,
A) two or more nuclei fuse or stick together to form a heavier nucleus that has exactly the same mass as the original nucleus
B) a heavy nucleus breaks apart into a number of smaller nuclei whose combined mass is less than the original nucleus
C) two or more nuclei fuse or stick together to form a heavier nucleus whose combined mass is slightly less than the original nucleus
D) two or more nuclei fuse or stick together to form a heavier nucleus whose combined mass is slightly greater than the original nucleus