Astudy is created in which the participants of the study are unaware who received the treatment and who did not. which element of the experiment design is known to be a part of this study?

One of the complementary angles is 4 degrees mor than the other. find the angles (recall that complementary angles are angles whose sum is 90 degrees.) which of the following can not be used to solve the problem if x represents one of the angles? a. 2x-4=90 b. 2x+4=90 c. x+4=90