Let's consider a limited set of climate data, examining temperature differences in 1948 vs 2018.
we sampled 197 locations from the national oceanic and atmospheric administration's (noaa) historical data, where the data was available for both years of interest.

we want to know: were there more days with temperatures exceeding 90'f in 2018 or in 1948?

the difference in number of days exceeding 90'f (number of days in 2018 - number of days in 1948) was calculated for each of the 197 locations.
the average of these differences was 2.9 days with a standard deviation of 17.2 days.

we are interested in determining whether these data provide strong evidence that there were more days in 2018 that exceeded 90°f from noaa's weather stations.

(a) is there a relationship between the observations collected in 1948 and 2018? or are the observations in the two groups independent? explain.

(b) write hypotheses for this research in symbols and in words.

(c) check the conditions required to complete this test. a histogram of the differences is given to the right.

sorry not sure

step-by-step explanation:

hello!

to begin with, we're given that on earth, a rock weighs 20 pounds, and while on jupiter, that same rock weighs 42 pounds. now, we're trying to find the weight of a rock that weighs 10.5 pounds on earth, on jupiter.

to solve this, first, set up a proportion, cross-multiply, and solve it algebraically.

setting up the proportion is the hardest and the most confusing part of the problem, but it's simple.

if on earth, the rock weighs 20 lbs, and on jupiter it weighs 42 lbs, our first part of our proportion is 20/42 lbs. the second part has to be equal to each other. this means that 10.5 has to be on the numerator of the fraction, and x, the value we're trying to find, has to be on the denominator. remember that the rock weighs 10.5 lbs on earth, and we're trying to find the weight of it on jupiter (which is x).

20/42 = 10.5/x

next, you would cross-multiply.

20x = 42(10.5)

20x = 441

now, solve it algebraically by using division.

x = 22.05 lbs

this can be rounded to 22.1 lbs.

therefore, the weight of the rock on jupiter is 22.1 lbs, the fourth choice.

substitute,

circle 1 = 5

circle 2 = 20

circle 3 = 44

in this case no matter how you add, you will always get a perfect square..

hence proved

happy to

pls mark as brainliest

2 equivalent expressions to represent the area of a rectangle and the top is n-3 and the side is 2

area of the rectangle = length * width

given length = n - 3

width = 2

replace it in the area

so area of the rectangle = (n-3) *2

= 2(n-3)

one of the expression is 2(n-3)

to get another expression we distribute 2 inside the parenthesis

2(n-3) is 2n - 6

so another expression is 2n - 6

two equivalent expression are

2(n - 3)   , 2n - 6