Table schema:
CREATE TABLE table_name_40 (k_2_o INTEGER, al_2_o_3 VARCHAR, objects VARCHAR, na_2_o VARCHAR, fe_2_o_3 VARCHAR)

Question: What is the highest K 2 O, when Na 2 O is greater than 1.87, when Fe 2 O 3 is greater than 0.07, when Objects is Ritual Disk, and when Al 2 O 3 is less than 0.62?
SQL: SELECT MAX(k_2_o) FROM table_name_40 WHERE na_2_o > 1.87 AND fe_2_o_3 > 0.07 AND objects = "ritual disk" AND al_2_o_3 < 0.62