The key answer of exercise 8

Q1 → The first sentence is the topic sentence.

Q2 → The writer omitted these points related to motivation:

• you learn about specialty areas
• because of growing up with a deaf parent / relative
• the desire to ensure equal opportunities for the hearing impaired

Note that another writer might prioritise things differently, and there's no single 'right' answer.

Q3

• Firstly
• Additionally
• Furthermore