CREATE TABLE "chemical_composition_of_warring_states_a" (
  "objects" text,
  "date" text,
  "si_o_2" real,
  "al_2_o_3" real,
  "fe_2_o_3" real,
  "k_2_o" real,
  "na_2_o" real
);

Question: What is average SiO 2, when Na 2 O is 7.53, and when Al 2 O 3 is less than 2.13?
SQL: SELECT AVG("si_o_2") FROM "chemical_composition_of_warring_states_a" WHERE "na_2_o"=7.53 AND "al_2_o_3"<2.13;

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 "chemical_composition_of_warring_states_a" WHERE "na_2_o">1.87 AND "fe_2_o_3">0.07 AND "objects"='ritual disk' AND "al_2_o_3"<0.62;

Question: What is the highest SiO 2, when K 2 O is greater than 0.16, when Fe 2 O 3 is greater than 0.16, and when Na 2 O is less than 7.53?
SQL: SELECT MAX("si_o_2") FROM "chemical_composition_of_warring_states_a" WHERE "k_2_o">0.16 AND "fe_2_o_3">0.16 AND "na_2_o"<7.53;