Freddy the frog is climbing up a well. every day he climbs up 3 m but some nights he falls asleep and slips back 4m at the start of the 16th day he has climbed a total of 29 m. on how many nights was he asleep?

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.