Is diet or exercise effective in combating insomnia? Some believe that cutting out desserts can help alleviate the problem, while others recommend exercise. Forty volunteers suffering from insomnia agreed to participate in a month-long test. Half were randomly assigned to a special no-dessert diet; the others continued desserts as usual. Half of the people in each of these groups were randomly assigned to an exercise program, while the others did not exercise. Those who ate no desserts and engaged in exercise showed the most improvements.

a) type of experimental design

b) if blocked, what blocked by

c) experimental units

d) factor(s) and levels

e) treatments

f) response variable

g) was blinding used

h) how randomization & replication is used