1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Morgarella [4.7K]
2 years ago
12

A firecracker shoots up from a hill 140 feet high, with an initial speed of 100 feet per second. Using the formula H(t) = −16t2

+ vt + s, approximately how long will it take the firecracker to hit the ground?
A: Five seconds
B: Seven seconds
C: Nine seconds
D: 11 seconds
Mathematics
2 answers:
V125BC [204]2 years ago
6 0
<span>H(t) = −16t^2 + vt + s

</span>
<span>H(t) = −16t^2 + 100t + 140

H(t) = 0 = </span><span>−16t^2 + 100t + 140

16t^2 - 100t -140 = 0

t = [100 +/- √ (100^2 -4(16)(-140) ) ] /(2(16))

t = 7.43 and t = - 1.18.

El que tiene sentido para la pregunta es t = 7.43 s.

Option B) 7 s (approximately)


</span>
denis-greek [22]2 years ago
3 0

Answer: it’s b, 7 seconds. Just took the test

Step-by-step explanation:

You might be interested in
A random sample of 85 group leaders, supervisors, and similar personnel revealed that a person spent an average 6.5 years on the
strojnjashka [21]

Answer:

<em>95% of confidence interval for the Population</em>

<em>( 6.1386 , 6.8614)</em>

Step-by-step explanation:

<u><em>Step( i ):-</em></u>

<em>Given random sample size 'n' =85</em>

<em>Mean of the sample size x⁻ = 6.5 years</em>

<em>Standard deviation of Population = 1.7 years</em>

<em>Level of significance = 0.95 or 0.05</em>

<u><em>Step(ii):-</em></u>

<em>95% of confidence interval for the Population is determined by</em>

<em></em>(x^{-} - Z_{0.05} \frac{S.D}{\sqrt{n} } , x^{-} + Z_{0.05} \frac{S.D}{\sqrt{n} })<em></em>

<em></em>(6.5 - 1.96\frac{1.7}{\sqrt{85} } , 6.5 + 1.96 \frac{1.7}{\sqrt{85} })<em></em>

<em>( 6.5 - 0.3614 , 6.5 + 0.3614 )</em>

<em>( 6.1386 , 6.8614)</em>

<u><em>Conclusion</em></u><em>:-</em>

<em>95% of confidence interval for the Population</em>

<em>( 6.1386 , 6.8614)</em>

8 0
3 years ago
How do i do this problem
dezoksy [38]
X*y=y/b........................
7 0
2 years ago
Which expression is equivalent to 4×4×4×4?
Lady bird [3.3K]
8*4 
I hope that helps !
So, 4*4*4*4 = 16+16 which is 32
4 0
2 years ago
Plz help fast. What is the value of x?
beks73 [17]

Answer is 7.b  because of the angles

3 0
2 years ago
John's car is stopped at a red light. When the light changes, the car accelerates to 45 miles per hour in 15 seconds. What is th
Ede4ka [16]
Initial velocity of John's car (V1) = 0 miles per hour
Final velocity of John's car (V2) = 45 miles per hour
Time taken for acceleration = 45 seconds
Then
Acceleration = (V2 - V1)/Time taken
                     = (45 - 0)/15 miles per hour per second
                     = 45/15 miles per hour per second
                     = 3 miles per hour per second.
So the approximate rate of change in the miles per hour that John's car accelerated is 3 miles per hour per second. The correct option among all the options given in the question is option "A".

5 0
2 years ago
Read 2 more answers
Other questions:
  • Use the Remainder Theorem to find the remainder when f(x) = x^4 + 4x^3 - x^2 - 16x -12 is divided by x - 4.
    9·1 answer
  • How many shirts must be purchased so that the cost is the same for both companies
    8·1 answer
  • Write a polynomial function of least degree with integral coefficient that has the given zeros. -2, 2, 4, and 6
    6·1 answer
  • The sum of 5 consecutive integers is 505. what is the third number in this sequence
    7·2 answers
  • 5x + 10+5(x+2) distributive property <br> (Just simply)
    13·1 answer
  • Find a primitivism root of 6
    7·1 answer
  • Help anyone pleaseLol
    13·1 answer
  • Use the Intermediate Value Theorem to show that there is a root of the given equation in the specified interval.
    12·1 answer
  • Determine what type of model best fits the given situation: every day half a bacterial population dies
    14·1 answer
  • Can someone please help tell me answer please!!!!!!
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!