The solar terms in the northern hemisphere are

(1) According to the principle of revolution, around June 22nd, the sun shines directly on the Tropic of Cancer, and the solar term in the northern hemisphere is summer.

(2) At this time, the sun shines directly on the Tropic of Cancer.

(3) When the sun shines directly on the Tropic of Cancer, the day is the longest and the night is the shortest in the northern hemisphere, and the night is the longest and the day is the shortest in the southern hemisphere.

(4) At this time, there will be an extreme day in the Arctic Circle and an extreme night in the Antarctic Circle.

(5) According to the chart, point A is on the equator with latitude of 0.

So the answer is: (1) 6; 22; Summer solstice;

(2) Tropic of Cancer;

(3) The shortest day and the longest night;

(4) extreme day;

(5)0 .