Shaping and calculating Be value for a 30 second burst

I have a question about determining the Be for generic traffic shaping.
I've looked through the QoS exam guide, QoS configuration guide, the doc cd
and haven't seen enough to be able to figure this one out.

AR - 1.544 mb
Cir - 768k
Tc - 125 ms
burst for 30 sec up to line rate

I understood Be to be AR - Cir.

The answer key for this task states that the Be is calculated by taking
the line rate and multiplying it by 30 sec?

1544000bps*30s = 46320000bits

There's just no way to put that many bits on the wire in 1 sec. Or is the
Be the number of tokens to be replenished in 1 sec ( same as 5790000
bits/Tc)

And while I am at it, if you've found a good reference please pass it on.

-- 
r/
LG
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