The following queries produce the same results.

select customer_name, customer_city
from customer, salesman
where customer. salesman_id = salesman. salesman_id
and salesman. lname = 'SMITH';

select customer_name, customer_city
from customer
where customer. salesman_id =
(select salesman_id
from salesman
where lname = 'SMITH')

a. True.
b. False