Table: formula_one_1998
Columns: entrant
constructor
chassis
engine
tyre
driver
rounds

Question: Who was the constructor for a FW20 chassis?
SQL: SELECT "constructor" FROM formula_one_1998 WHERE "chassis" = 'fw20'

Question: What engine did David Coulthard have in his mp4-13 chassis?
SQL: SELECT "engine" FROM formula_one_1998 WHERE "chassis" = 'mp4-13' AND "driver" = 'david coulthard'