How many times was Sanger 3730xl $2400 usd?
CREATE TABLE "comparison" (
  "sequencer" text,
  "ion_torrent_pgm" text,
  "454_gs_flx" text,
  "hi_seq_2000" text,
  "so_li_dv4" text,
  "pac_bio" text,
  "sanger_3730xl" text
);
SELECT COUNT("ion_torrent_pgm") FROM "comparison" WHERE "sanger_3730xl"='$2400 USD';