CREATE TABLE "type_metal_alloys_mentioned_in_the_uk_mo" (
  "sn_sb_pct" text,
  "liquidat_c" real,
  "solidat_c" real,
  "hardness_brinell" real,
  "purpose" text
);

Question: What is the sum of Solidat (c) that's purpose is display type, heavy duty jobs, and a hardness (brinell) is smaller than 33?
SQL: SELECT SUM("solidat_c") FROM "type_metal_alloys_mentioned_in_the_uk_mo" WHERE "purpose"='display type, heavy duty jobs' AND "hardness_brinell"<33;

Question: When the Sn/Sb (%) of 13/17, and a Liquidat (c) bigger than 283 what's the solidat (c)?
SQL: SELECT SUM("solidat_c") FROM "type_metal_alloys_mentioned_in_the_uk_mo" WHERE "sn_sb_pct"='13/17' AND "liquidat_c">283;

Question: How many Liquidat (c) have a purpose of dual (machine & hand composition)?
SQL: SELECT COUNT("liquidat_c") FROM "type_metal_alloys_mentioned_in_the_uk_mo" WHERE "purpose"='dual (machine & hand composition)';