The area is perimeter times height plus area of the bases
Answer:

Step-by-step explanation:
Given



Required
Determine 
From laws of probability, we have:

Substitute in values


Hence,
<em> is calculated to be 0.557</em>
Answer:
b. Invalid, because the sample may not be representative of the population.
Step-by-step explanation:
A sample of around 10% of the population is needed to be representative.
In this question:
We have a population of 500,000, and a sample of 10,000.
10,000/500,000 = 1/50 = 0.02 = 2% of the population, so not representative, and option b is correct.
What you have written down is correct, x=-3