Savannah plans to conduct a study that involves cosmetics. She wanted to know the preference of cosmetic use among adolescents, young adult, middle adult and the late adult women. The research design of her study would be

Descriptive research design

Step-by-step explanation:

Descriptive research design is a type of quantitative research design that tends to describe/depict the current status (condition) of a particular variable or phenomenon. In the case above, the research is quantitative because it deals with quantifiable data, which is the preference(quantity) of cosmetics. Savannah wanted to describe the preference of cosmetic use among adolescents, young adult, middle adult and the late adult women, which makes it a descriptive research design. It does not involve conducting experiment, or generating correlations etc.

Therefore, it is a Descriptive research design

ANSWER

B. 12

EXPLANATION

The given triangle is isosceles, because two of the arms are equal.

The angles directly under these two arms and the base are equal.

Therefore the three angles of the isosceles triangle are

84°, 4x°,4x°

The sum of these angles is 180°

Group similar terms,

Divide both sides by 8

The correct choice is B.