Standardized tests for certain subjects, given to high school students, are scored on a scale of 1 to 5. Let X represent the score on a randomly selected exam. The distribution of scores for one subject’s standardized test is given in the table. A 2-column table with 5 rows. Column 1 is labeled score with entries 1, 2, 3, 4, 5. Column 2 is labeled probability with entries 0.18, 0.20, 0.26, 0.21, 0.15.

What is the standard deviation of the distribution?

1.3
1.6
1.7
2.5

Unaware that 35% of the 10000 voters in his constituency support him, a politician decides to estimate his political strength. a sample of 200 voters shows that 40% support him. a. what is the population? b. what is the parameter of interest? state its value c. what is the statistics of the interest? state its value d. compare your answers in (b) and (c) is it surprising they are different? if the politician were to sample another 200 voters, which of the two numbers would most likely change? explain