Answer:
A.) Blocking occurs in an experiment when a certain experimental unit is divided or split into groups based on a certain criteria. In the experiment above, the experiment was blocked for class of runner, either professional or recreational. This is essential in other to limit the possible variability in our experiment. It is very possible thatvtve response of each class of runner may differ, therefore, it good practice to block for class of runner in other to contain the variation.
B.) Randomizing the type of shoe being worn by the runner ensures that we have given each runner an equal chance of selecting any type of shoe available,thereby eliminating biases which might emanate from fixing shoe type for each runner.
C.) Replication could simply be defined as the application of a certain treatment on more than one experimental unit. In the experiment above, by blocking for class of runner, hence having the professional and recreational units, and treatment applied to each experimental unit, Hence giving the experimenter the chance of controlling variation in the experiment.
Step-by-step explanation:
Answer:
C. 
A. First Picture
Step-by-step explanation:
We are given the inequality, 
.
On simplifying the inequality, we get,
i.e.
i.e. 
i.e. 
So, we get the correct representations of the inequality are,
C.
A. the First Picture
