Answer:
<h3>The option C) 15 s is correct</h3><h3>Therefore the maximum height it reaches in <u>15 seconds. </u></h3>
Step-by-step explanation:
Given equation is 
Given that a projectile is thrown upward so that its distance above the ground after t seconds is
<h3>To find how many seconds does it reach its maximum height:</h3>
"The standard form of a parabola's equation is expressed as :
.
If 
, then the parabola opens upwards;
if 
the parabola opens downwards."
The maximum height is the vertex of the parabola which is 
.
Comparing the given equation with the standard form of parabola we get
the values of a=-13 , b=390 and c=0
The maximum height in 
.
Substitute the values we get
<h3>∴ t=15 s</h3><h3>∴ The option C) 15 s is correct.</h3><h3>∴ the maximum height is the vertex of the parabola, at t reaches in 15 seconds. </h3>
The type of numbers, rational and irrational from the numbers Keisha writes are;
a. Rational numbers; -9, 3.0, 2, and 2.42
b. Irrational numbers; √8
<h3>What is the difference between rational and irrational numbers?</h3>
Rational numbers are numbers are numbers that can be expressed as a ratio of two whole numbers P/Q, in which, <em>Q </em>≠ 0
Irrational numbers are those that cannot be expressed as a fraction P/Q
The given numbers are;
-9, √8, 3.0, 2, 2.42
- √8 = 2•√2 (√2 cannot be expressed as a fraction of two whole numbers)
a. The rational numbers are therefore;
b. The irrational number is; √8
Learn more about rational and irrational numbers here:
brainly.com/question/43641
#SPJ1
The upper quartile is, Q1, is 45. The lower quartile, Q2, is 85. The interquartile range is 40. I hope this helps!
Answer:
25%
Step-by-step explanation:
40000 - 100%
10000 - x
x=25%
B
I do hope this is right please forgive me if this is wrong.
