The main purpose of random selection is to

a. make it easier to obtain a statistically significant result

b. help the experimenter figure out what caused the observed behavior

c. ensure that your sample accurately represents the population

d. decrease the probability of a Type I error

2. A researcher thinks that their growth treatment will help kids grow up to be bigger and stronger. They administer the treatment to 10 Males at age 4and then measure their height at age 18 years We know the average height for an 18 year old is 68 inches tall. The data for the children is as follows 68, 70, 74, 76, 75, 66, 67, 68, 70, 70. Use proper program and use this info to answer the questions below. All answer must have 2 decimal places

What test is this?

what is independent variable and dependent variable.

what is null hypothesis?