The half-life of helium-5 is 7.6 × 10-22 seconds, and the half-life of helium-9 is 7 × 10-21 seconds. Approximately how many times greater is the half-life of helium-9 than that of helium-5?
A.
2 times
B.
7 times
C.
9 times
D.
11 times

Amira is painting a rectangular banner 2 1/4 yards wide. the banner will have a blue background. amira has enough paint to cover 1 1/2 square yards of the wall. the school colors are blue and yellow, so amira wants to add yellow rectangles on the left and right sides of the blue rectangle. the yellow rectangles will each be 3/4 yards wide and the same height as the blue rectangle. what will be the total area of the two yellow rectangles?

Find the root(s) of f (x) = (x- 6)2(x + 2)2.

Parallelogram rstu is a rhombus. m∠r = 120° what is m∠t = 120 (what is m∠rsu? )