Which two steps should a developer take to accomplish this?

A Salesforce org has more than 50,000 contacts. A new business process requires a calculation that aggregates data from all of these contact records. This calculation needs to run once a day after business hours.

Which two steps should a developer take to accomplish this? Choose 2 answers
A . Use the @future annotation on the method that performs the aggregate calculation.
B. Implement the schedulable Interface In the class that contains the aggregate calculation method.
C. Use the areadOnly annotation on the method that performs the aggregate calculation.
D. Implement the Queuable Interface in the class that contains the aggregate calculation method.

Answer: B,D