An airplane flies 40km directly south in 10 minutes and 20 km directly east in five minutes, its average speed is: a)2.98km/min
b)2km/min
c)8km/min
d)4km/min

Ineed with these last two questions: 1) what are two types of cold air masses that influence the weather in north america? name them and describe their humidity. 2) describe the motion of a cold air mass and a warm air mass and the weather you would expect at a warm front and an occluded front.

Name three different units of energy used to measure heat and describe what type of situations each is usually used.

What is created when solids, liquids, an gases mix with one another