What makes Washington’s central and eastern geographic regions unique?

Washington 's central and Easter geographic region are said to be  unique due to its differences in cultivation.Central Washington is almost plains region, with to rolling hills in the east. The rich volcanic soil , manure and dry weather creates an environment which  is ideal for agriculture procedures and manufacturing food . It is observed that more than 300 crops are grown in Eastern region of  Washington.

I'm hella smart but i dont know that

Just do the math, then think