Final answer:
The location at 23.5N receives the most direct sunlight around June 21, which is known as the summer solstice. The latitude that experiences the Sun at its zenith at noon on the first day of summer is called the Tropic of Cancer.
Step-by-step explanation:
The location at 23.5N receives the most direct sunlight around June 21, which is known as the summer solstice. On this date, the Sun shines down most directly upon the Northern Hemisphere, appearing about 23° north of the equator. The latitude that experiences the Sun at its zenith at noon on the first day of summer is called the Tropic of Cancer.