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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.

An isosceles trapezoid with a perimeter of 42 inches. each of the congruent non parallel sides is 5 inches long, and the trapezoid is 3 inches tall. how long are the two parallel sides? a. 10 in, 22 in b. 16 in, 16 in c. 10 in, 16 in d. 12 in, 20 in

Tom and lilly rented a house for $12,000 last year. at the start of the year they bought the house they had been renting directly from the owner for $250,000. they believe they could rent it for $12,000 this year, but stay in the house. how much does tom and lilly’s decision to buy the house change gdp? a. it reduces gdp by $12,000 b. it does not change gdp c. it raises gdp by $238,000 d. it raises gdp by $250,000