R2 and Back Row Attack - Whistle?

[timasdf]

Hi Antonio (and anyone else that can add to this discussion),

I don't doubt that the R2 should be prepared to whistle a BRA/BRB, if the R1 does not. However, I cannot find any specifics mandating the R2's whistle in the Rule Book or Case Book.

The following quiz question adds to the uncertainty...

Q. The second referee should whistle and give a signal for:

1. Illegal alignment of players on the serving team at the moment of serve.
2. Ball out of bounds for an antenna fault on the second referee's side of the net.
3. Back-row player violations.
4. All of the above.

Clearly, #1 is no (not R2's responsibility).
Clearly, #2 is yes (must be whistled).

The "no" in #1 eliminates #4 from being an option.

#3 then becomes suspect, especially given the lack of clear responsibility to "whistle," when the case book only lists "determine."

Any thoughts?