CREATE TABLE "power_stations" (
  "name" text,
  "year_commissioned" real,
  "gross_head_metres" real,
  "installed_capacity_megawatts" real,
  "average_annual_output_million_k_wh" real
);

Question: What is the earliest Year commissioned wiht an Average annual output greater than 58 and Installed capacity of 20?
SQL: SELECT MIN("year_commissioned") FROM "power_stations" WHERE "average_annual_output_million_k_wh">58 AND "installed_capacity_megawatts"=20;

Question: What is the Average annual output for Culligran power station with an Installed capacity less than 19?
SQL: SELECT AVG("average_annual_output_million_k_wh") FROM "power_stations" WHERE "name"='culligran' AND "installed_capacity_megawatts"<19;

Question: What is the Year Commissioned of the power stationo with a Gross head of less than 18?
SQL: SELECT AVG("year_commissioned") FROM "power_stations" WHERE "gross_head_metres"<18;

Question: What is the Year commissioned of the power station with a Gross head of 60 metres and Average annual output of less than 59 million KWh?
SQL: SELECT MAX("year_commissioned") FROM "power_stations" WHERE "gross_head_metres"=60 AND "average_annual_output_million_k_wh"<59;