Answer: have each experimenter test randomized blocks of conditions.
Step-by-step explanation:
Randomized block design is a technique used in controlling nuisance in an experiment due to excessive variables, experimental conditions, etc which can make the experiment complex/ complicated.
Answer:a=b/2-c/2
b=9+a
b=-2a
Step-by-step explanation:
C, because 7 divided by 9 is 7/9
Hope this helps!