Merchants are the parties providing the products or services
Does this mean like for movies, free movie premiere tickets? or free hotel stay? or free gourmet experience? Who wouldn't want to be a helper?
Helpers are those who are hired by Lina to make the reviews for the advertisers or merchants. They are paid so i think there will be more applicants to be employed as helpers.
Helpers are the qualified users who are being paid from advertising revenue (up to 50%) to post quality reviews. If they didn't post a quality review within two months. I think they will be demoted.