Respuesta :

so it cooks for 2 hrs and 20 minutes......and it has to be done by 1 pm.

so from 1 p.m. - 2 hrs = 11 a.m........- 20 minutes = 10:40 a.m

start cooking at 10:40 a.m. and it will be done by 1 p.m
 the answer is 10:40 a.m.