Find n(A) for the set. A={-6, -5, -4, ..., 0}
A. n(A) = 7
B. n(A) = 6
C. n(A) = 4
D. n(A) = 1

Can someone me and do the problem plz so i can understand it more better

Heather is writing a quadratic function that represents a parabola that touches but does not cross the x-axis at x = -6. which function could heather be writing? fx) = x2 + 36x + 12 = x2 - 36x - 12 f(x) = -x + 12x + 36 f(x) = -x? - 12x - 36

Three numbers x, y, and z are in the ratio 2: 7: 8. if 12 is subtracted from y, then three numbers form a geometric sequence (in the order x, y–12, z). find x, y, and z. there are 2 sets.