CREATE TABLE "faculty_and_staff" (
  "data" text,
  "headcount" real,
  "percent_of_total" text,
  "less_than_25_000" text,
  "25_000_to_40_000" text,
  "40_000_to_50_000" text,
  "50_000_to_60_000" text,
  "60_000_to_70_000" text,
  "70_000_to_80_000" text,
  "more_than_80_000" text,
  "mean" text
);

Question: What's the sum of the headcounts that have an n/a value of $60k to $70K?
SQL: SELECT SUM("headcount") FROM "faculty_and_staff" WHERE "60_000_to_70_000"='n/a';

Question: What's the mean of the $70-80k ones that have 2.80%?
SQL: SELECT "mean" FROM "faculty_and_staff" WHERE "70_000_to_80_000"='2.80%';

Question: Which have more than $80k and a total percent of 2.2%?
SQL: SELECT "more_than_80_000" FROM "faculty_and_staff" WHERE "percent_of_total"='2.2%';

Question: What's the total percent of the $40-50K ones that have n/a?
SQL: SELECT "percent_of_total" FROM "faculty_and_staff" WHERE "40_000_to_50_000"='n/a';