"<span>Rust Belt" is a term for upper Northeastern United States region and other like the Great Lakes, and the Midwest States, referring to economic
decline, population loss, and urban decay due to the shrinking
of its once powerful industrial sector.</span>
It belongs to the lithosphere
Air masses can<span> bring anything from tropical warm and humid days to arctic cold depending on the type of it.</span><span> Fronts form the boundaries of </span>air masses<span> with differing properties.
;)</span>
The perceptible natural movement of the air, especially in the form of a current of air blowing from a particular direction
I think the answer is d not a 100 % sure
