The following set of ordered pairs gives the results of a science exper iment. Twelve people were given different daily doses of vitamin C, in milligrams, for a year. This is the x-value. They reported the num ber of colds they got during the year. This is the y-value. (100, 4), (100, 4), (100, 3), (250, 3), (250, 2), (250, 2),
(500, 1), (500, 2), (500, 1), (1,000, 1), (1,000, 2), (1,000, 1)
a. Construct a scatterplot.
b. Describe the correlation.
c. Should the scientists label the vitamin C intake the explanatory variable and the number of colds the response variable? Explain

im sorry but no. i just need to answer for 50 poonts oof

3. parallelogram

step-by-step explanation:

we turn each of our sides into direction vectors

ab=b-a=(3 - 7, 1 - 0) = (-4, 1)

bc=c-b=(1,6)

cd=d-c=(4,-1)

da=a-d=(-1,-6)

we see how the opposite sides have negated direction vectors; this is characteristic of a parallelogram.   we have congruent sides ab=cd and bc=da with unequal lengths because 1^2+6^2 is different from (-4)^2+1^2.   so it's not a square or a rhombus.  

we check the dot product of direction vectors of adjacent sides.   we have

ab dot bc = -4(1) + 1(6) = 2

that's not zero so the sides are not perpendicular.   we've ruled out rectangle.

the direction vectors indicate two pairs of congruent parallel sides, so we choose parallelogram over trapezoid.