Give the full name of the actor with the highest rental rate.
full name refers to first_name, last_name; the highest rental rate refers to max(rental_rate)
SELECT T1.first_name, T1.last_name FROM actor AS T1 INNER JOIN film_actor AS T2 ON T1.actor_id = T2.actor_id INNER JOIN film AS T3 ON T3.film_id = T2.film_id ORDER BY T3.rental_rate DESC LIMIT 1