Answer:
Lower, low pressure
Step-by-step explanation:
The temperature at equator are mostly higher than at the poles almost all times of year. This high temperature causes air at the equator to warm up quickly and thus, the air density reduces and it becomes lighter. Now, light air rises upwards. Thus, creating a low pressure region at equators. This low pressure causes the air near the poles gush towards the equator.
Hence, the blanks will be filled with the words
Lower, low pressure.