These are easy and multiple choice so please just answer the

These are easy and multiple choice, so please just answer them all so i don\'t have to leave negative feedback. Thanks

1. A random sample is one ______

a. That is haphazard

b. That is unplanned

c. In which every unit of a particular size has an equal probability of being selected

d. That ensures that there will be no uncertainty in the conclusions

2. The following distribution has:

a. A positive skew

b. A left skew

c. No skew

d. A negative skew

3. In an experiment on the effect of exercise on memory, the independent variable is: _____(choose only one answer)

a. Number of hours of exercise

b. Recall score on a memory test

c. Gender of the subjects

d. Gender of the experimenter

4. For the scores 3, 5, 8, 10, 14, 17, 21, 25, calculate the 75th percentile using the following formula: R = P/100 x (N + 1)

a. 6.75

b. 17

c. 21

d. 20

Solution

1)

c. In which every unit of a particular size has an equal probability of being selected

2)

d. A negative skew

3)

a. Number of hours of exercise

4)

75 / 100 * (8+1) = 6.75

a. 6.75