Answer:
all work is shown and pictured
a. The population for the study is a total of 1000 adults, so the 50% that favored the plan made up a total of 500 people, since 500 is 1/2 (or 50%) of 1000.
b. The percentage provided is an inferential statistic. Inferential statistics are made by taking a sample of a population and using that sample as data used to make inferences/predictions. Since the percentage provided is a sample of a population being used to make a prediction, it is an inferential statistic.
Answer:
The simplified form is: 
Step-by-step explanation:
To simplify the expression given we, need to open the brackets, and if there is power term. Then we need to group all the like terms and then arrange in the descending order of powers of the given expression.
Now the expression that is given to us is:

Here we will simplify it by grouping the like terms, as follows:

So this is the required simplified form.