$1.$ Find average product $($item$)$ price.

$2.$ Find the total number of orders by each city. Display city names by order counts.

$3.$ Find the total number of orders by each customer.

a$.$ Display result by cid attribute.

b$.$ Display result by fname and lname attributes.

$4.$ Calculate and display order prices for customer $298.$ Display order id and order price values.

$5.$ List the cities which had orders on $01-01-2009$ and $01-01-2010.($Use division operation$)$

$6.$ Find all addresses for customer $298.$ Display all address details. $($Use division operation$)$

$7.$ Find the customers who ordered the most expensive item$($s$).$ Display only the customer$$s full names.