What is the file format of data storage in HBase?

Regarding the basic operation of Hive table building, which of the descriptions is correct?

In the process of using Flume to transmit data, in order to prevent the loss of data due to the restart of the Flume process, which of the following Channel types can be used? (Multiple choice)

Spark is a memory-based computing engine. All data during the running of Spark programs can only be stored in memory.

In the Fusioninsight HD cluster three-tier network, the management node, control node, and data node are recommended to be installed in different network segments to improve reliability.