Step-by-step explanation:
the average rate of change of a function f in an interval [x-low, x-high] is
(f(x-high) - f(x-low)) / (x-high - x-low)
the year 2000 means t = 2000-1980 = 20
the year 2015 means t = 2015-1980 = 35
so, we have
(A(35) - A(20)) / (35 - 20)
((-0.6(35)² + 37.2×35 + 243) - (-0.6(20)² + 37.2×20 + 243)) / 15
((-735 + 1302 + 243) - (-240 + 744 + 243)) / 15
(810 - 747) / 15 = 63/15 = 4.2
the average change rate between 2000 and 2015 is 4.2.
that means that the use of nuclear energy in the USA increased by 4.2 billions of kilowatt hours per year during that period.
Answer: A
Step-by-step explanation:
1x20=20
2x10=20
4x5=20
Answer:
27 chickens
Step-by-step explanation:
A chicken farmer also has cows for a total of 30 animals
Both animals have a total of 66 legs
Let a represent the number of chicken
Let b represent the number of cows
a + b= 30........equation 1
Since a chicken has only two legs and a cow has four leg then, the expression can be represented as
2a + 4b= 66........equation 2
From equation 1
a + b= 30
a = 30-b
Substitute 30-b for a in equation 2
2a + 4b= 66
2(30-b) + 4b= 66
60 - 2b + 4b= 66
60 + 2b= 66
2b= 66-60
2b= 6
b= 6/2
b= 3
Substitute 3 for b in equation 1
a + b = 30
a + 3=30
a= 30-3
a= 27
Hence the farmer has 27 chickens
V1=(T1/T2)*V2
In this problem, since you are given no actual numbers, the only thing you can do is multiply V2 over to get V1 alone. Since you can't cancel anything out, you are left with the answer above.