user: Question: What is the average share at 8:00 P.M., and an 18-49 of 1.3/4 with an air date of April 4, 2008?
Columns: ['Air Date', 'Timeslot', 'Rating', 'Share', '18-49', 'Viewers', 'Weekly Rank']
Types: ['text', 'text', 'real', 'real', 'text', 'real', 'text']
Sample row: ['February 22, 2008', '9:00 P.M.', 4.6, 8.0, '2.4/7', 7.44, 'TBA']
SQL:

assistant: SELECT AVG("Share") FROM "Table" WHERE "Timeslot" = '8:00 P.M.' AND "18-49" = '1.3/4' AND "Air Date" = 'April 4, 2008';