Question

Sarah wants to know which brand of nail polish lasts the longest without chipping.She buys 4 types of nail polish - Essie (which she normally uses,) butter, OPI, and Sally Hanse. Every Sunday for 4 weeks she paints her nails with a different brand of nail polish and records how many days she lasts before she gets her first chip. She makes sure to use the same bottom coat and top coat with each types of nail polish, and she makes sure to do the same weekly routine each week so that her nails aren't getting treated more roughly

different weeks.

1. Independent variable:


2. Dependent variable:


3. Hypothesis:


4. Control group:


5. Experimental group:


6. Constants:

Answer 1

The independent variable in Sarah's experiment is the brand of nail polish, the dependent variable is the days until first chip, and her hypothesis could be that a specific brand outlasts the others. There is no explicit control group, and constants include the same base and top coats, as well as a consistent weekly routine.

Step-by-step explanation:

In Sarah's experiment to determine which brand of nail polish lasts the longest without chipping, the independent variable is the brand of nail polish used (Essie, butter, OPI, and Sally Hanse), because this is the factor that is being changed to observe its effect on the dependent variable. The dependent variable is the number of days the nail polish lasts without chipping, as this is the outcome that is measured in response to the independent variable. A possible hypothesis could be 'OPI nail polish will last the longest without chipping compared to Essie, butter, and Sally Hanse brands.'

There is no explicit control group in this experiment because each brand of nail polish is being tested individually across different weeks; however, Essie could be considered a baseline or control reference since it is the brand Sarah normally uses. The experimental group consists of the nails painted with butter, OPI, and Sally Hanse since they are being tested against Sarah's usual brand. The constants in the experiment include the same bottom and top coat used for each nail polish, as well as Sarah's weekly routine.

Answer 2

1. Independent variable : the input variable that can be changed and controlled.
the nail polish on Sarah's nails
2.Dependent variable: values that result from the independent variables.
days the nail polish lasts
3. Hypothesis: Different types of nail polish last different period of time without chipping.
4. Control group:the independent variable is held constant in this group and is not exposed to changes.
the time Sarah paints her nails (Sarah paints her nails every Sunday for 4 weeks)
the type of bottom coat and top coat (she uses the same bottom coat and top coat with each types of nail polish)
weekly routine (she makes sure to do the same weekly routine each week so that her nails aren't getting treated more roughly different weeks. )
Experimental group: the independent variable is changed for the experimental group
type of nail polish (Essie, Opi and Sally Hanse)
6. Constants: the person who does the experiment (Sally), period of research (one week), her weekly routine, bottom coat and top coat,