Ill give 20 points. Leonie wants to collect information on the length of time pupils at her school spend on homework each evening. She thinks that this depends on the school year, so her sample should contain some pupils from each year group. What information does Leonie need in order to be able to select a stratified sample?

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

c.the first excerpt shows their expectations about the camp, and the second shows the reality of their circumstances

is the answer this is because first they talk about what is expected of the camp but in the second excerpt they get a harsh awakening to the true realities of the camp.

hope this

i would appreciate brainliest : )

the answer is -81 is the answer