Fill in the blanks with the correct answer.
1. The northern parts of North America are ............. than the southern parts.
2. The ................ cause rain throughout the year along the north – west coast in the northern part of North America.
3. The ................ warms the Alaskan Coast and keeps it frost-free in winter.
4. The tropical regions mainly experience rainfall in the .............. season.
5. The prairies are a vast stretch of ............ grasses.