In geology, a graded<span> bed is one </span>characterized by<span> a systematic change in grain or clast size from one side of the bed to the other. Most commonly this takes the form of normal grading, with coarser sediments at the base, which grade upward into progressively finer ones.</span>
I believe the answer is: natural resources
East of the Rocky Mountains is the so called Midwest region in North America. This vast region is mostly consisted of lowlands covered with grasses, and they are bordered with mountain ranges on both the east and the west, which prevents the maritime influence.
Because of this natural barriers, this region has mostly continental air masses influencing its climate. In the colder period of the year they are continental polar air masses, forming over Canada and moving southwards. In the warmer period of the year they are continental tropical, forming in the southern part of this region and moving northwards.
This type of air masses bring in very hot and dry summers, and very cold and snowy winters.
Explanation:
Earthy forms of hematite are typically red to reddish brown and often called 'Red Ochre'. These earthy varieties are also very soft and can be scratched by a fingernail.
A polar region tilted away from the sun has six months of winter darkness. It is almost night there for 6 months straight.
