Answer:
Sample size is 
Step-by-step explanation:
Given that,
Margin of error
%
Confidence level
%
Suppose, sample proportion
i.e. 
We know that,
Margin of error 
∴ 





squaring on both side,
∴ 
Hence, the sample size is,

Hence, the correct option is 
The toy rocket hits the ground when h(t) = 0.
So, h(t) = 0 = -9t^2 + 81.
Solving the equation,
-9t^2 = -81
Dividing by -9
t^2 = 9
Taking the square root.
t = 3
The answer is 3 seconds.
Answer:
A general line can be represented as , y= m x + c
And general equation of circle is , ax²+by²+2 g x +2 f y +c=0
Now there are following possibilities
1. A line and circle have no common point of intersection, that is no solution.
2. A line may be a tangent to a circle, that is one common point, one solution.
3. A line may intersect a circle maximum at two points, that is 2 solution.
Image is depicted below.
Answer: Last one is right C = 5 / 9 (F-32)
Step-by-step explanation: Solving C from equation F = (9/5)C + 32 :
1. multiply by 5 you get 5F = 9C + 160 and 5(F-32) = 9C
2. divide by 9 you get (5/9) (F-32) = C
It comes from integrating by parts twice. Let

Recall the IBP formula,

Let


Then

Apply IBP once more, with


Notice that the ∫ v du term contains the original integral, so that



