The area of the U. S. that stretches east from the Rocky Mountains to the Mississippi River is the:

Great Plains

Explanation:

The Great Plains are found between the Mississippi River and the Rocky Mountains. It is an expanse of basically flat grasslands found in ten U.S states.

it's a secular holiday. it is and was a custom developed to recognize the ending of a time and a wish for a good future. the kind of kiss you exchange, if you are single, is intended to predict what kind of year you will have in the coming year.

it is saying good bye to the last year with all its ups and downs, and hello to the new year, with all its hopes and dreams.