Which aspect of Apex programming is limited due to multitenancy?

A developer wants to import 500 Opportunity records into a sandbox. Why should the developer choose to use data Loader instead of Data Import Wizard?

Cloud kicks has a multi-screen flow that its call center agents use when handling inbound service desk calls.
At one of the steps in the flow, the agents should be presented with a list of order numbers and dates that are retrieved from an external order management system in real time and displayed on the screen.
What should a developer use to satisfy this requirement?

Which three data types can a SOQL query return? Choose 3 answers

A developer has the following requirements:
Calculate the total amount on an Order.
Calculate the line amount for each Line Item based on quantity selected and price.
Move Line Items to a different Order if a Line Item is not stock.
Which relationship implementation supports these requirements?