Tom asked the 20 members of the football squad at his school how long they spent on the internet by evening. 7 of them spent over 4 hours per evening online.
Tom used this information to estimate how many of the 1200 students at his school spent over 4 hours per evening on the internet.
a.) Assuming that tom is good with numbers, what was his estimate?
b.) Write down one thing that could be done to make the estimate more reliable.

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.

squares, rhombus, rectangles