Table: golftournament_results
Columns: no
date
tournament
winning_score
to_par
margin_of_victory
runner_s_up

Question: Name the margin of victory when the number is 15
SQL: SELECT "margin_of_victory" FROM golftournament_results WHERE "no" = 15

Question: Name the number of numbers for howard clark
SQL: SELECT COUNT("no") FROM golftournament_results WHERE "runner_s_up" = 'Howard Clark'

Question: Name the margin of victory when tournament is algarve open de portugal
SQL: SELECT "margin_of_victory" FROM golftournament_results WHERE "tournament" = 'Algarve Open de Portugal'

Question: Name the tournament when margin of victory is 3 strokes and winning score is 71-66-70-67=274
SQL: SELECT "tournament" FROM golftournament_results WHERE "margin_of_victory" = '3 strokes' AND "winning_score" = '71-66-70-67=274'