$11.$ With the Customers table still open, create a multiple$-$field index as described below:

a$.$ Use Location as the name of the index. $($Hint: Be careful not to include spaces after the index name.$)$

b$.$ Use the State field, sorted in Descending order, as the first field in the index.

c$.$ Use the City field, sorted in Ascending order, as the second field in the index. Save the changes to the Customers table and then close it$.$