What minimum size of block volume with Balanced performance tier maximizes throughput for large files?

A customer has decided to use Oracle Cloud Infrastructure (OCI) for their Disaster Recovery (DR) site for an on-premises Hadoop cluster. They have an RPO of 4 hours, and an RTO of 1 hour.
Which two options should they consider on OCI to meet their DR requirements?

You are running a cluster using multiple BM.Standard2.52 machines. The model is on a NFS share running on block volume- You've tried doubling the number of machines but It's not running any faster.
Which two actions could potentially speed up this tightly coupled workload?

Which statement Is correct about deleting an Instance Pool?