Abag contains two red marbles and five blue marbles. you draw a marble, record its color, replace it, and then draw a second marble. what is the probability that you draw a blue marble at least once? a.0.28 b.0.49 c.0.71 d.0.92

2+5 = 5 total marbles

 5 are blue so you have a 5/7 chance of picking blue each time

5/7 = 0.714 rounded to 0.71

d. 0.92

Step-by-step explanation:

Given : Number of blue marbles in bag = 5

Number of red marbles in the bag = 2

Total marbles in bag= 5+2=7

Since,  we draw a marble, record its color, replace it, and then draw a second marble.

It means every outcome is independent of each other.

Now, the probability that you draw a blue marble at least once = 1- P(no blue marble drawn)

=

Hence, the probability that you draw a blue marble at least once= 0.92

Hence, the correct answer is d. 0.92 .

256π units²   (answer b)

step-by-step explanation:

the formula for the surface area of a sphere of radius r

is             a = 4πr²

and so, if r = 8 units, then the surface area is:

a = 4π(8 units)² = 256π units²   (answer b)

the answer is two. hope this !