Answer:

Step-by-step explanation:
3 envelopes having 2 red card
2 envelopes having 1 red card and 1 black card
1 envelope having 2 black cards
We are given that . An envelope is selected at random and a card is withdrawn and found to be red.
So, No. of ways of envelope having red card = 3+2 = 5
No. of required ways of envelope having 1 red card and 1 black card = 2
So, probability of getting an envelope having 1 red card and 1 black card = 
Hence The chance the other card is black is 
Answer: 91,445,760 ft³
Step-by-step explanation:
You know that the base of this pyramid is a square, then you can use the following formula to calculate its volume:

Where "s" is the lenght of any side of the base of the pyramid and "h" is the height of the pyramid.
You know that:

Then, you can substitute these values into the formula. So, you get that the volume of The Great Pyramid is:

The volume of a cylinder is
(pi) (radius²) (height) .
Radius = 1/2 diameter.
Radius of this pool = (1/2) (18 ft) = 9 ft
The pool is a cylinder with height of 4.5 feet.
The water in it is also a cylinder, but only 4 ft high.
Volume of the water =
(pi) x (radius²) x (height)
= (pi) x (9 ft)² x (4 ft)
= (pi) x (81 ft²) x (4 ft)
= (pi) x (324 ft³) = 1,017.9 ft³ .