1. In the CCIE lab exam,When redistributing into eigrp, with no metric specified...is it safe to use any metric?
2. When told to configure PIM...does that mean sparse-dense-mode?
2) you need to understand what type of PIM to develop from the context and the scenario description: no fixed rule can be expected at this level.
sparse-dense-mode can be useful if you are required to use autoRP protocol for RP mapping, but there are alternatives to this (autorp listener ?) and boostrap protocol doesn't need it.
1) My personal opinion: you need to demonstrate good knowledge of theory so for example you should know that the last parameter is an MTU value and so a reasonable value is 1500 and not 1(bytes).
the MTU is present in a field of the EIGRP external IP route TLV data structure.
Hope to help