It is a function because every input has exactly one output. It passes the vertical line test.
If you plotted another point at 2 hours it would no longer be a function bc 2 would be an input they had more than one output.
-1 1/3 over -1/3
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Answer: (A) 30%
Step-by-step explanation:
Given : The probability that a bird will lay an egg =0.75
The probability that the egg will hatch =0.50
Now, the probability that the egg will lay an egg and hatch = 
Also,The probability that the chick will be eaten by a snake before it fledges =0.20
Then, the probability that the chick will not be eaten by a snake before it fledges : 1-0.20=0.80
Now, the probability that a parent will have progeny that survive to adulthood will be :-

Hence, the probability that a parent will have progeny that survive to adulthood = 30%
Height of the stack = 3 fourth of an inch
=
× (1 inch)
Height of 180 cards =
× (1 inch)
Thickness of 1 card =
×
× (1 inch)
=
× (1 inch)
I think it is the third choice