1. Maybe Tom realized that there is great profit potential in narcotics. (I mean, drugs are big, even today.) Maybe he thought that if they didn't get into the narcotics business, the other families would gain more money and power. Maybe if the other families had more money and influence, then they would try to challenge the Corleone Family's dominance. Hence Tattaglia coming after them.

2. I don't think Connie would have been nearly as upset. Carlo wasn't very nice to her, after all, and she loved her brother, Sonny. If she knew that Carlo was involved in Sonny's death she might have somewhat accepted Michael's actions.

3. My first reaction (before I became a psycho MICHAEL CORLEONE WORSHIPPER) was, "Oh my God! He killed poor Fredo!" (My current reaction is, "Fredo, you betrayed my beloved Michael. Curse you, Fredo.")

4. This is a toughy. It's hard to tell. Sollozzo might have thought it was some kind of excuse or a plot to mislead him.

5. (I won't answer this one because I haven't seen Part III in sooooooo long.)

Those are just my thoughts. I'm probably wrong about some things... lol

That was fun. cool

"Be discreet in all things, and so render it unnecessary to be mysterious about any." - Arthur Wellesley, 1st Duke of Wellington