Couple more trig questions.

A)Could someone briefly explain to me what the general solution to a trig equation is and how to find it?

ex: sin(x/2)=SqRt(3)/2

I have a couple of these questions and have no idea how to solve for them.

B)"The Sun rises at 9:17 on December 21 and at 4:35 on June 22. There is no Daylight savings time, so the time the sun rises on any other date can be predicted from a sinusiodal graph with a period of 365 days. Write a sinusiodial equation that relates the time the sun rises to the day of the year"

I can't seem to wrap my head around this one because it's worded, someone care to help me with it?