Last year the Debate Club had 7 members. This year there are 9 members in the club. Estimate the percent change inthe number of club members. Which is the best estimate for the percent change in the number of club members?

B) 28% increase

Explanation:

There are 2 extra members because 9-7 = 2

Divide this change (2) over the original amount (7) to get the approximate value of 2/7 = 0.2857 which converts over to roughly 28.57%

That rounds to 29%, but that isn't listed. So I'd go with 28% instead. The estimate is close enough.

b

Step-by-step explanation:

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.