Find the standard form of the equation of the parabola with a vertex at the origin and a focus at (0, -7).
select one:
a. y = -1/7 x^2
b. y^2 = -7x
c. y = -1/28 x^2
d. y^2 = -28x

How many heads would you expect if you flipped a coin twice? first, fill in the table below with the correct probabilities. hint: the sample space for flipping a coin twice is {hh, ht, th, tt}. a = b = c = f