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Answer:
A=950
B=540
Step-by-step explanation:

Answer: this is difficult
Step-by-step explanation:
Answer:
115
Step-by-step explanation:
because 6 & 7 will add up to 180
so if 7 = 65
then 180 - 65 = 115
#6 = 115
Answer:
The population density is 0.364 fish per gallon.
Step-by-step explanation:
The population density can be defined as the number of individuals (in this case, small tropical fish) per unit of area or volume. In this case, the volume of the aquarium (55 gallon).
The density can be calculated then as:

The population density is 0.364 fish per gallon.