Dear Student,
1) Wet clothes take longer time to dry on a humid day because the air is full of water vapour. Hence, the evaporation becomes slow making the clothes to take longer time to dry up.
2)Amount of insolation decreases from equator towards poles because insolation comes through vertical rays of the sun. Thus, it covers less space but we feel more heat. When the sunrays, moves from equator towards poles, they become slanting.The slanting rays have to travel more distance and that is why even if they cover more space, the amount of heat felt is less.
Regards.