Answer:
C. 20
Step-by-step explanation:
The order in which the members are selected is important. The first one selected is the president and the second is the vice president.
So we use the permutations formula to solve this question.
Permutations formula:
The number of possible permutations of x elements from a set of n elements is given by the following formula:
In this problem:
2 people are going to be chosen from a set of 5. So
So the correct answer is:
C. 20
Answer:
a) The maximum amount of water the aquarium can hold is 1728 in³.
b) The cover has to be 624 in² big.
Step-by-step explanation:
a) The maximum volume of water that the aquarium can have is the same as the volume of the aquarium:
V=L×W×H=18 in × 8 in × 12 in= 1728 in³
b) The protective covering is used on the four walls of the aquarium. We have to find the areas of the four walls:
One of them is given by the multiplication of the width and the height:
A₁= W×H= 8 in × 12 in=96 in²
The other area is given by the multiplication of the length and the height:
A₂= L×H= 18 in × 12 in= 216 in²
As the fish aquarium is rectangular the area of the walls is given by:
=2×96 in²+2×216 in²=624 in²