Answer:
As per the statement:
The path that the object takes as it falls to the ground can be modeled by:
h =-16t^2 + 80t + 300
where
h is the height of the objects and
t is the time (in seconds)
At t = 0 , h = 300 ft
When the objects hit the ground, h = 0
then;
-16t^2+80t+300=0
For a quadratic equation: ax^2+bx+c=0 ......[1]
the solution for the equation is given by:

On comparing the given equation with [1] we have;
a = -16 ,b = 80 and c = 300
then;


Simplify:
= -2.5 sec and
= 7.5 sec
Time can't be in negative;
therefore, the time it took the object to hit the ground is 7.5 sec
If it is exactly 90 degrees you are looking for, your answer would be, 3:0:0. Which is 3:00.
The midpoint formula is x1+x2 over 2 and y1+y2 over 2. When you use it to find the midpoint of (0,-8) and (-4,10), you get (-2,1).
Slope formula is y2-y1 over x2-x1, which will give you -6.
Sorry it took me so long, the correct answer is B.
Answer:
68%
Step-by-step explanation:
The Standard Deviation Rule = Empirical rule formula states that:
68% of data falls within 1 standard deviation from the mean - that means between μ - σ and μ + σ.
95% of data falls within 2 standard deviations from the mean - between μ – 2σ and μ + 2σ.
99.7% of data falls within 3 standard deviations from the mean - between μ - 3σ and μ + 3σ.
From the question,
Step 1
We have to find the number of Standard deviation from the mean. This is represented as x in the formula
μ = Mean = 61
σ = Standard Deviation = 8
For x = 53
μ - xσ
53 = 61 - 8x
8x = 61 - 53
8x = 8
x = 8/8
x = 1
For x = 69
μ + xσ
69 = 61 + 8x
8x = 69 - 61
8x = 8
x = 8/8
x = 1
This falls within 1 standard deviation of the mean where: 68% of data falls within 1 standard deviation from the mean - that means between μ - σ and μ + σ.
Therefore, according to the Standard Deviation Rule, the approximate percentage of daily phone calls numbering between 53 and 69 is 68%