Answer:
C.) each treatment is thought of as a value of the explanatory variable
Step-by-step explanation:
The main purpose for using randomization in an experiment is to control the lurking variable and establish a cause and effect relationship.
If we do not control lurking, or confounding, variables, we cannot accurately establish a cause and effect relationship; this means we cannot ensure that each treatment is a value of the explanatory variable.
Answer:
Draw a vertical line passing through (-3,0)
Steven needs a total of 320 points to have a mean score of 80
Steven has 245 points so far
Steven needs to score at least 75 points on his last test to qualify for the team