A researcher wants to compare the effect of a new type of shampoo on hair condition. The researcher believes that men and women may react to the shampoo differently. Additionally, the researcher believes that the shampoo will react differently on hair that is dyed. The subjects are split into four groups: men who dye their hair; men who do not dye their hair; women who dye their hair; women who do not dye their hair. Subjects in each group are randomly assigned to the new shampoo and the old shampoo. This experiment

a. has three factors (shampoo type, gender, whether hair is dyed).
b. has two factors (shampoo type and whether hair is dyed) blocked by gender
c. has one factor (shampoo type), blocked by gender and whether hair is dyed.
d. has two factors (gender and whether hair is dyed) blocked by shampoo type.
e. is completely randomized. (Old exam question)

This experiment has three factors (shampoo type, gender, whether hair is dyed)

Step-by-step explanation:

the researcher is trying to make a comparison between an old shampoo and a new on and also was gender sensitive as she considers their hair coloration too because it affects the result slightly.

he right the guy above me is valid

Step-by-step explanation:

for the friend request.

when a figure, such as triangle (xyz) is reflected over the line y = x to create x'y'z' the x-coordinates and y-coordinates of the original image (pre-image) will be reversed for the image. (e.g., (x, y) > (y, x)) this means that the pre-image position of the x- and y-coordinates switch places which in turn provides a mirror like image of the original xyz.  

i notice that when i draw a line segment from x to x', that the points are parallel from each other -- they are exactly across from each other and do not intersect with any other points.  

yes, think i would see the same characteristic if you drew the line segment connecting y with the reflecting line and then y' with the reflecting line because of the essence of reflections. because it is a mirror image, each point was effected the same way which leads me to conclude that they same would apply to y and y'.