A researcher designs an experiment to test a new memory medication. She received the names of 1,000 individuals willing to participate in her study. She plans to study 250 people. To reduce experimenter bias, what procedure must be used when choosing the participants? a
Deception

b
Naturalistic observation

c
Random assignment

d
Random sampling

e
Research accountability

This was a series of articles written to persuade new york to ratify the constitution.

Which scenario is least likely to occur in a market economy? a) the government pays farmers to stop planting certain crops for a period of time. b) the government stops a factory from producing imitations of an expensive type of purse. c) the government offers tax breaks to companies that meet efficiency goals in their products. d) the government allows only two competitors to offer goods for sale on the country's highways.

The biome pictured above is found in areas such as kenya and south africa. the land is grass-covered with very few trees and gazelles and other grazers are common here. why does this biome have a low population of trees? a) large grazing animals destroy the trees. b) it is a deforested rainforest with poor soil. c) it has high temperatures and low precipitation. d) it has a long rainy season followed by flooding.