Scientists at a major pharmaceutical firm investigated the effectiveness of an herbal compound to treat the common cold. They exposed each subject to a cold virus, then gave him or her either the herbal compound or a sugar solution known to have no effect on colds. Several days later they assessed the patient's condition using a cold severity scale ranging from 0 to 5. They found no evidence of benefits associated with the compound, a. Identify if it is an observational study or an experiment Identify b. the subjects studies c. the factor in the experiment and the number of levels for each d. the number of treatments e. the response variable measured f. the design(completely randomized, blocked or matched) g. whether is waws blind or double bind h. the nature and scope of the conclusion the study can reach