A researcher studies the relationship between the number of hours of sleep per night and the performance on a memory test. Study participants are randomly selected to get no sleep or
sleep in 1-hour increments, up to 8 hours total (that is, the participant gets 1 hour, 2 hours, and
so on, up to 8 hours of sleep). The researcher determines that the association between the
two variables can be modeled with the linear equation p = 9h +15, where his number of hours
of sleep and p is the percentage score on the memory test.

boxplot e is the answer

for this case we have that by definition, the surface area of a cylinder is given by:

where:

r: it is the radius of the cylinder

h: it is the height of the cylinder

we can also rewrite it as:

where:

la: it's the lateral area

ba: area of the base

option a

x^2 + 81

we can factor this using difference of square binomials.

rewrite the equation:

x^2 - (-81)

factor:

(a^2 - b^2) = (√a^2 + √b^2)(√a^2 - √b^2)

(x^2 - (-81) = (x + √-81)(x - √-81)

we can remove the - from under the radical by multiplying it by i.

(x^2 - (-81) = (x + i√81)(x - i√81)

(x^2 - (-81) = (x + 9i)(x - 9i)

we can check our answer by using foil:

x^2 - 9ix + 9ix - 81i^2

x^2 - 81^2

i^2 = -1

x^2 + 81