Answer:
a) Abigail accuses Proctor of witchcraft after he confesses to their affair
c) Abigail fakes having visions just in time to avoid suspicion on herself
Step-by-step explanation:
When Proctor confesses having had an affair with Abigail, and how now she wants his wife to die so she can take her place, Abigail denies it all, claiming that is he who lies and connives with the devil. She even fakes an attack on the other girls and herself, by Mary´s spirit, just in time to avoid any suspicions falling on her.