CREATE TABLE table_9320 ("Length feet  ( m ) " TEXT, "Width feet  ( m ) " TEXT, "Load short tons  ( MT ) " TEXT, "Truss type ( s ) " TEXT, "Year built" TEXT, "Source  ( Year ) " TEXT)

What is the width for hte truss with a source of zacher (1994)?
SELECT "Width feet (m)" FROM table_9320 WHERE "Source (Year)" = 'zacher (1994)'
SELECT "Width feet (m)" FROM "table_9320" WHERE "Source (Year)" = 'zacher (1994)'