A bag contains 3 black marbles and 5 white marbles. Paul picks a marble at random from the bag and replaces it back in the bag. He mixes the marbles in the bag and then picks another marble at random from the bag. Calculate the probability that Paul picks: A. Two black marbles
B. Black marble in his second draw

id go with B.

you'd get a mix because its bound to happen.

for finding the midpoint of any given 2 pair of points simply add the respective x coordinates with other x coordinate and the y coordinate with other y coordinate and divide them by 2

in your question it will be :

(3+1)/2 for the x coordinate of mid point i.e 2

[8+(-4)]/2 for the y coordinate of midpoint i.e 2

so coordinates of mid point of points (3,8) and (1,-4) will be (2,2)

your answer is  

d.

196.5 m2

step-by-step explanation: