<h2><u>
Answer with explanation</u>
:</h2>
Let
be the average life of light bulbs.
As per given , we have
Null hypothesis : 
Alternative hypothesis : 
Since
is right-tailed and population standard deviation is also known, so we perform right-tailed z-test.
Formula for Test statistic : 
where, n= sample size
= sample mean
= Population mean
=population standard deviation
For
, we have

Using z-value table , Critical one-tailed test value for 0.06 significance level :

Decision : Since critical z value (1.5548) < test statistic (1.6180), so we reject the null hypothesis .
[We reject the null hypothesis when critical value is less than the test statistic value .]
Conclusion : We have enough evidence at 0.06 significance level to support the claim that the new filament yields a longer bulb life
Answer:
1/2= 5/10
5/10 - 3/10 = 2/10 or 1/5
so planet X is 1/5 of a light-year closer
Step-by-step explanation:
4a + 3 - 9 = -7 + 2 + a
4a - 6 = -5 + a
4a - a = -5 + 6
3a = 1 / : 3
a = 1/3
The time taken by the rock will be 8.77 seconds.
<h3>What is speed?</h3>
Speed is defined as the ratio of the time distance traveled by the body to the time taken by the body to cover the distance.
Given that:-
The equation for free fall at the surface of some planet (s in meters, t in seconds) is s = 2.86t²
The time will be calculated by using the speed formula.
Speed = Distance \ Time
25.1 = 2.86t² \ t
t = 25.1 / 2.86
t = 8.77 seconds
Therefore the time taken by the rock will be 8.77 seconds.
To know more about Speed follow
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Answer:
Students should be able to find the x-intercepts of a quadratic function using both factoring and completing the square. All that should be given to students is the standard form of a quadratic equation in the form y = ax^2 + bx + c.
Step-by-step explanation: