A = false, it will take 0.031 cal to raise 1g Au 1degree while it will take 0.033 cal to raise 1g Hg 1 degree so, although Au will heat up faster, it will not be discernably faster so...
b = true
c = false, Au density > Hg
d = true
I'm not sure about the distance to the nearest star, but it's probably about 4 light-years (L-y).
1 L-y = 1.86 * 10E5 mi/sec * 3600 sec/hr * 24 hr/day * 365 day/yr
1 L-y = 5.9 *10E12 mi and 4 L-y = 2.3 *10E13 mi distance to star
2.3 * 10E13 mi / 900 mi/hr = 2.6 * 10E10 hr hours to star
2.6 * 10E10 hr / (24 hr/day) = 1.1 * 10E9 day days to star
1.1 * 10E9 day / 365 day/yr = 3 * 10E6 yr = 3 million years to star
Answer:

Explanation:
From conservation of energy states that

No temperature change occurs from heat transfer if ice melts and becomes liquid water (i.e., during a phase change). For example, consider water dripping from icicles melting on a roof warmed by the Sun. Conversely, water freezes in an ice tray cooled by lower-temperature surroundings.
Hope this helped you
I believe the answer is A) Less work in less time.