2. a psychologist is interested in testing the effects of a new drug on reducing depression. write down the hypothesis for this experiment. identify the independent variable, the dependent variable, an experimental group and control group.

H0 (null hypothesis): There is no difference in depression levels between the control and experimental group post-treatment.

Ha (alternative hypothesis): The experimental group has lower depression levels than the control group post-treatment.

Do note, that the hypotheses are tested after the experiment has been conducted, not before. What you are trying to prove is the Ha.  

Independent variable (IV): New drug

Dependent variable (DV): Depression

Experimental group: Individuals clinically diagnosed with depression (DV), who receive the new drug.  

Control group: Individuals clinically diagnosed with depression (DV), who don’t receive the new drug.  

Explanation:

From the description in the question, it is clear that the type of research that is going to be conducted is a form of experimental research. An experimental research, is a type of study where researchers test a hypothesis by keeping certain variables (dependent variables) constant while manipulating another set of variables (independent variables). The intent of this type of research design is to know whether an independent variable (IV) influences a dependent variable (DV), and if so, to which extent does the IV affect the DV. In experimental research designs, researchers are allowed to change the levels or types of IV – but the DV must remain constant.  

Experimental research designs, because of its nature, require at least two groups to compare and contrast. These can be the same groups of people, experiencing variations of the IV – also known as within-subject design. Or, it could be different groups of individuals with the same characteristics experiencing different variations of the IV – known as between-subject designs. The research above is a form of between-subject design, utilizing control group (those who do not receive the IV treatment) and experimental group (those who receive the IV treatment).

none because there is no words that describe a noun and give a mood

a source card is mage during research to tell the facts about the source one is using.