1) Explain the difference between multiple independent variables and multiple levels of independent variables. Which is better?
2) What is blocking and how does it reduce "noise"? What is a disadvantage of blocking?
3) What is a factor? How can the use of factors benefit a design?
4) Explain main effects and interaction effects.
5) How does a covariate reduce noise?
6) Describe and explain three trade-offs present in experiments.