Studies have shown that many people will experience improvement in their condition even if they are given a sugar pill or some other treatment that is known to be worthless. This can be controlled by . * A. making the study double-blind.
B. using a placebo on the control group.
C. treating the two groups, experimental and control. exactly alike
D. testing the significance of the statistical difference between the two groups, experimental and control.

An effective thesis statement will reflect . . 1) possible weaknesses in your own argument. 2) possible weaknesses in your opponent's argument. 3) the type of document--or genre--you plan to write. 4) your attitudes about aquatic mammals

Pls, i really need on this question?

The greatest gift the sumerians gave the world was the invention of writing. the sumerians were wealthy people. they needed some way to keep track of what they owned. they began drawing pictures. they used a reed as a pen. they drew on soft pieces of clay. the soft clay was then dried in the sun. the tablet became a permanent record. later, the sumerian drawings changed into wedge-shaped symbols. this kind of writing is called cuneiform. by putting symbols together, the sumerians could write entire sentences.