A. 314 sq cm
Explanation: pi•r^2
3.14 x 10^2
3.14 x 100 =314
70 or +70
To represent a positive integer
Answer:
The bird will be at a ground distance of 10.04 units away.
Step-by-step explanation:
Vertex of a quadratic function:
Suppose we have a quadratic function in the following format:

It's vertex is the point 
In which


Where

If a<0, the vertex is a maximum point, that is, the maximum value happens at
, and it's value is
.
Equation for the height:
The height of the bird after x seconds is given by:

Which is a quadratic equation with
.
When the bird is at its highest?
Quadratic equation with
, and thus, at the vertex. The ground distance is the x-value of the vertex. Thus

The bird will be at a ground distance of 10.04 units away.
A)

B)

We first find the z-score associated with the level of confidence. For 95% confidence:
Convert 95% to a decimal: 0.95
Subtract from 1: 1-0.95 = 0.05
Divide by 2 (this is the area in the tails): 0.05/2 = 0.025
Subtract from 1 (we don't want the tails, we want the area in the middle): 1-0.025 = 0.975
Using a z-table (http://www.z-table.com) we find the z-score for this is 1.96. We now use the formula

For a 98% confidence level:
Convert 98% to a decimal: 0.98
Subtract from 1: 1 - 0.98 = 0.02
Divide by 2: 0.02/2 = 0.01
Subtract from 1: 1 - 0.01 = 0.99
Using the z-table we see the closest number to this is for the z-score 2.33:
Answer:
Correct option: Third one
Step-by-step explanation:
Let's analyse each sentence:
"Both x = -8 and x = 8 are roots of f(x)"
False, we can't affirm that x = 8 is a root of f(x) with the information given.
"Neither x = -8 nor x = 8 is a root of f(x)"
False, because x = -8 is a root of f(x), because the factor (x + 8) would be zero, and it is multiplying the rest of the function, so the final value would be zero.
"f(-8) = 0"
True, because x = -8 is a root, and the factor x + 8 will be zero and will multiply the other factors of f(x)
"f(8) = 0"
False, because x = 8 is not a root of f(x)
So the correct option is the third one