Marina believes that high doses of caffeine slow a person's reaction time. to test this belief, she has five friends each drink three 8-ounce cups of coffee and hen measures their reaction time on a learning task. what is wrong with martina's research strategy?

Explain the difference between an independent and dependent sample. choose the correct answer below. a. in an independent sample, the individuals are chosen without replacement; in a dependent sample, the individuals are chosen with replacement. b. in a dependent sample, one would use a two-tailed hypothesis test; in an independent sample, one would use a one-tail hypothesis test. c. a sample is independent when an individual selected for one sample does not dictate which individual is to be in the second sample. a sample is dependent when an individual selected for one sample dictates which individual is to be in the second sample. d. a sample is independent when an individual selected for one sample dictates which individual is to be in the second sample. a sample is dependent when an individual selected for one sample does not dictate which individual is to be in the second sample. independent samples are often referred to as matched-pairs samples.

When analyzing the election of 1876, what conclusion can be drawn? a.a majority of northerners wanted to enforce reconstruction policies more stringently.b.if tilden had won the electoral votes from louisiana, florida, or south carolina, he would have been elected president.c.the republican party had increased its support in the south.d.rutherford hayes did poorly in the western states.e.the republican party did a good job protecting the voting rights of african-americans in mississippi.

Which of the following was a key accomplishment of the people of songhai? a. they had a strong military and became the largest empire in west africa. b. they established a center of islamic scholarship. c. they worked with iron and prospered from the gold-salt trade. d. they dominated in the trade of ivory, enslaved people, and animal skins.