Explanation
Contractors are external users who can access Field Service features such as work orders, service appointments, assets, products consumed, etc... There are two types of contractor licenses available:
Contractor (Full Access) and Contractor (Limited Access). Contractor (Full Access) licenses allow users to access all Field Service features except scheduling optimization. Contractor (Limited Access) licenses allow users to access only work orders assigned to them or their crew members via mobile app or web browser[22.
Universal Containers should deploy 25 Contractor (Full Access) licenses to contractors who need to schedule resources and 75 Contractor (Limited Access) licenses to contractors who need access to work orders, assets, mobile app, and chatter. References:
https://help.salesforce.com/s/articleView?id=sf.field_service_contractors_overview.htm&type=5
https://help.salesforce.com/s/articleView?id=sf.field_service_contractors_license_types.htm&type=5
https://help.salesforce.com/s/articleView?id=sf.field_service_contractors_full_access_license_features.htm&type
https://help.salesforce.com/s/articleView?id=sf.field_service_contractors_limited_access_license_features.htm&

Explanation
Pinned statuses prevent service appointments from being rescheduled or unscheduled by scheduling and optimization services3. Status transitions define the valid status changes for service appointments based on business rules. References: 3 https://help.salesforce.com/s/articleView?id=sf.fs_pinned_statuses.htm&type=5
https://help.salesforce.com/s/articleView?id=sf.fs_status_transitions.htm&type=5

Explanation
This option allows applying different prices for the same product based on the customer agreement, and avoids duplicating products that have standard prices. References:
https://help.salesforce.com/s/articleView?id=sf.fs_price_books.htm&type=5

Explanation
This option allows automatically associating certain products to Work Orders based on the work type selected, and generating Work Order Line Items for those products. References:
https://help.salesforce.com/s/articleView?id=sf.fs_work_types.htm&type=5

Explanation
Service Appointments are records that track the date, time, duration, and assigned resource for a work order or work order line item[117]. Creating a new Service Appointment for each site visit would allow Universal Containers to track when Technicians need to visit a customer site multiple times to resolve an issue by creating different service appointments for the same work order and capturing notes and status updates for each service appointment. Creating a new Child Work Order for each site visit would create unnecessary records and complexity. Child Work Orders are work orders that are related to another work order as part of a hierarchy[118]. Creating a new Product Consumed for each site visit would not track the site visits. Products Consumed are records that track the products or parts that are used or installed during a service appointment[119]. Creating a new Work Order Line Item for each site visit would not track the site visits.
Work Order Line Items are records that track specific tasks or products related to a work order[120].
References: https://help.salesforce.com/s/articleView?id=sf.fs_service_appointments.htm&type=5
https://help.salesforce.com/s/articleView?id=sf.fs_work_orders.htm&type=5
https://help.salesforce.com/s/articleView?id=sf.fs_products_consumed_overview.htm&type=5
https://help.salesforce.com/s/articleView?id=sf.fs_work_order_line_items.htm&type=5