Can someone help me??

He concluded that a heavier object dropped from the same height as a lighter object will land

Ascientist wants to use a model to present the results of his detailed scientific investigation. why would a model be useful? a )because the model makes the concepts easier to understand b) because the model is easy to put together and to use c) because the model prevents other scientists from asking questions d) because the model requires the audience to pay full attention to it i don't know what to choose because between a and d a is much more likely than d because it only wants to get the attention of the audience. i'm confuse.

The hockey team has been great! in 2008 they won 20% more games than in 2007. in 2009 they won 50% more games than in 2008. what was their overall percentage increase from 2007 through 2009?