Помогите пожалуйстаComplete each sentence with a verb in the correct form,

Помогите пожалуйста
Complete each sentence with a verb in the correct form, - ing or to...
1. After hours of negotiating, we managed ........an agreement.
a) to reach b) reaching
2. He gave up .........at University after he got the job.
a) studying b) to study
3. Julia is interested in........ her own business.
a) starting b) to start
4. I have decided ........from my work.
a) resigning b) to resign
5. They must increase the salary ....... the right applicants.
a) to attract b) attracting
6. We should finish......... the software before giving it to users.
a) testing b) to test