1. Because AB is the equator and A=C= 18, this line is a dark line. After drawing the complete map, we can see that the days in the northern hemisphere are long and the nights are short, so it is the solstice of summer. . .

2. The equatorial difference is11km, and AB = 3300 km, that is, AB is 30 degrees, that is, it is two hours. And because c is 18, two hours add up to 20 hours. ...