During the day, the sun heats up both the ocean surface and the land. The wind will blow from the higher pressure over the water to lower pressure over the land causing the sea breeze. The sea breeze strength will vary depending on the temperature difference between the land and the ocean. At night, the roles reverse.
If I understand the drawing correctly than yes, because 6 9/12 + 6 9/12 = 12 and 18/12 = 13 and 6/12 or 13 and 1/2. 13 1/2 + 4 8/12 = 13 6/12 + 4 8/12 = 17 and 14/12 = 18 2/12 or 18 and 1/6.
