Solved by a verified expert:Questions2. Does epinephrine have the same aggregating effect when the scale is pretreated with yohimbine(an alpha-1/2 adrenergic antagonist)? What about when the scale is pretreated with propranolol(a beta adrenergic antagonist)?3. What do the effects (or lack of effects) of yohimbine and propranolol suggest regarding the type of adrenergic receptors mediating catecholamine-induced pigment aggregation?