Question

1. a hand sanitizer was advertised to be more effective at killing bacteria than any antibacterial soap. students were evenly into 4 groups to test this claim. groups 1 - 3 washed their hands using the assigned hand sanitizer or soap (see table) and warm water for two minutes, and then dried their hands with a paper towel. group 4 rubbed their hands vigorously for 2 minutes in warm water, without any soap or sanitizer, and then dried their hands with a paper towel. after washing, each students hands were swabbed and the swab was applied to a culture plate and incubated. finally the bacterial cultures were counted.

(se anunciaba un desinfectante de manos que era más eficaz para eliminar las bacterias que cualquier jabón antibacterial. se dividió a los alumnos en 4 grupos para comprobar esta afirmación. los grupos 1 - 3 se lavaron las manos con el desinfectante o jabón de manos asignado (véase la tabla) y agua caliente durante dos minutos, y después se secaron las manos con una toalla de papel. el grupo 4 se frotó las manos enérgicamente durante 2 minutos en agua caliente, sin jabón ni desinfectante, y después se secó las manos con una toalla de papel. después de lavarse las manos, cada alumno se las frotó con un hisopo, que se aplicó a una placa de cultivo y se incubó. por último, se contaron los cultivos bacterianos. )

a. what are the independent and dependent variables in this experiment? (2 pts) (¿cuáles son las variables independiente y dependiente en este experimento? (2 puntos))
iv:________________________ dv:________________________
b. what is the control group? (1 pt) (¿cuál es el grupo de control? (1 pto))
control group (grupo de control):__________________________
c. list 3 constants. (3 pts) (enumera 3 constantes. (3 puntos))
1)
2)
3)
d. based on the results in the data table, was the advertisement supported or rejected? explain your answer. (2 pts) (basándote en los resultados de la tabla de datos, ¿apoyas o rechazas el anuncio? explica tu respuesta. (2 puntos))

Explanation:

a. The independent variable (IV) is the type of hand - cleaning product (hand sanitizer, Soap A, Soap B, warm water). The dependent variable (DV) is the number of bacteria (bacteria growth).
b. The control group is the group that does not receive the treatment being tested. In this case, Group 4 (warm water) is the control group as it has no soap or sanitizer.
c. Constants are factors that remain the same throughout the experiment.

1. Washing/drying time (2 minutes washing, then drying).
2. Incubation conditions (after swabbing, the swab is applied to a culture plate and incubated).
3. Drying method (using a paper towel).

d. The advertisement claimed that the hand sanitizer is more effective at killing bacteria than any antibacterial soap. Group 1 (hand sanitizer) had 30 bacteria, while Group 3 (Soap B) had 12 bacteria. Since Soap B (an antibacterial soap) had fewer bacteria than the hand sanitizer, the advertisement is rejected.

Answer:

a. IV: Type of hand - cleaning product (hand sanitizer, Soap A, Soap B, warm water); DV: Number of bacteria (bacteria growth)
b. Control Group: Group 4 (warm water)
c. 1) Washing/drying time; 2) Incubation conditions; 3) Drying method
d. The advertisement is rejected. Group 1 (hand sanitizer) had 30 bacteria, while Group 3 (Soap B, an antibacterial soap) had 12 bacteria. Since an antibacterial soap (Soap B) had fewer bacteria than the hand sanitizer, the claim that the hand sanitizer is more effective than any antibacterial soap is not supported.