How much did the the player with first name Len and last name Barker earn between 1985 to 1990 in total?
select sum(t1.salary) from salary as t1 join player as t2 on t1.player_id = t2.player_id where t2.name_first = 'Len' and t2.name_last = 'Barker' and t1.year between 1985 and 1990;