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