what two purposes does the Ethernet protocol use physical addresses?

For what two purposes does the Ethernet protocol use physical addresses? (Choose two.)

A.
to uniquely identify devices at Layer 2

B.
to allow communication with devices on a different network

C.
to differentiate a Layer 2 frame from a Layer 3 packet

D.
to establish a priority system to determine which device gets to transmit first

E.
to allow communication between different devices on the same network

F.
to allow detection of a remote device when its physical address is unknown

Explanation:
In computing, a physical address, also real address, or binary address, is the memory address
that is electronically (in the form of binary number) presented on the computer address bus

circuitry in order to enable the data bus to access a particular storage cell of main memory.
In a computer with virtual memory, the term physical address is used mostly to differentiate from a
virtual address. In particular, in computers utilizing memory management unit (MMU) to translate
memory addresses, the virtual and physical address refer to address before and after MMU
translation, respectively.