Step 1 :This question is about understanding the difference between independent samples and dependent samples (matched pairs) in statistics. Independent samples are those where the two samples are not related or paired in any way, while dependent samples are those where the samples have been paired in some way.
Step 2 :a. Comparing the incomes of 40 Democrats and 70 Republicans: This is an independent samples situation because the incomes of Democrats and Republicans are not paired in any way.
Step 3 :b. Comparing the LDL cholesterol for 50 soccer players and 50 basketball players: This is also an independent samples situation because the LDL cholesterol levels of soccer players and basketball players are not paired in any way.
Step 4 :c. Comparing how many hours 70 students spend studying per week to how many hours they spend on their smartphone per week: This is a dependent samples (matched pairs) situation because the hours spent studying and the hours spent on the smartphone are paired for each student.
Step 5 :d. Comparing the days hibernated by 45 black bears in California and 45 polar bears in Alaska: This is an independent samples situation because the hibernation days of black bears and polar bears are not paired in any way.
Step 6 :Final Answer: a. Independent Samples b. Independent Samples c. Matched Pairs d. Independent Samples