The sample space is nothing but ALL possible outcomes. In this case you have Black & Red id's. Then the sample space is {black, red}
We know that the ocean floor has a depth of 247 ft, and we also know that the diver is<span> underwater at depth of 138 ft, so its distance from the ocean floor will be:
</span>

ft
<span>
Now, the </span>rock formations rises to a peak 171 to above the ocean floor, so to find <span>how many feet below the top of the rock formations is the diver, we are going to subtract the distance to the driver form the ocean floor from the rock formations height:
</span>

ft
<span>
We can conclude that the diver is 62 feet </span><span>
below the top of the rock formations.</span>
Let rs.5 denominations be x , then rs 10 denominations will be 90-x
then total amount 5x + 10(90-x) which is rs.500
5x + 10(90-x) = 500
900 - 5x = 500
400 = 5x
therefore x = 80
therefore no. of rs.5 is 80
no. of rs.10 is 90-x = 90-80 = 10