A flag blows near a sea in the direction of the wind as shown in the figure below.

 If the flag is blowing during the day then the sea must be in which direction? 

• During the day, the air above the land heats up quickly due to the process of convention. 
• Due to this the air pressure above the land drops and the wind starts blowing from the high air pressure region of the sea to the land.
• In the given figure, the flag is blowing towards the east, which means the wind must be coming from the west side.
• Therefore, the sea must be on the west side of the flag.

Hence, west is the correct answer.