Susan Brown
The two questions that you missed are both based on the video at the end of Unit 3, on the heat generated by the loose connection.
Have you rewatched that video, writing down the calculations for yourself?
There are basically two steps.
1. Find the circuit current. (Remembering that the current will be the same throughout the circuit, and is determined by the total resistance in the circuit.)
2. Find the heat generated by the loose connection, using the circuit current and the resistance of that loose connection.