Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE table_17778 ( "Sequencer" text, "Ion Torrent PGM" text, "454 GS FLX" text, "HiSeq 2000" text, "SOLiDv4" text, "PacBio" text, "Sanger 3730xl" text )

### Question ###
What is 454 gs flx when pacbio is 100-500 mb?

### Accurate SQL ###

SELECT "454 GS FLX" FROM table_17778 WHERE "PacBio" = '100-500 Mb'