When a long-period comet is farthest from the sun in its orbit, which features of the comet exist? select all that apply.
a. coma
b. gas tail
c. nucleus
d. dust trail

When a comet is close to the sun, the force from the sun's radiation pushing against the comet making a dust and/or gas tail. The comet being close to the sun also forms the coma of a comet due to it's radiation. The only thing that doesn't exist while being close to the sun is the nucleus. In conclusion, When a long period comet is farthest from the sun in its orbit, C. the Nucleus exist.

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