<h2><u>
Answer with explanation</u>
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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:
Step-by-step explanation:
The scenario is represented in the attached photo. Triangle ABC is formed. AB represents her distance from her base camp. We would determine BC by applying the law of Cosines which is expressed as
a² = b² + c² - 2abCosA
Where a,b and c are the length of each side of the triangle and B is the angle corresponding to b. It becomes
AB² = AC² + BC² - 2(AC × BC)CosC
AB² = 42² + 28² - 2(42 × 28)Cos58
AB² = 1764 + 784 - 2(1176Cos58)
AB² = 2548 - 1246.37 = 1301.63
AB = √1301.63
AB = 36.08 km
To find the bearing, we would determine angle B by applying sine rule
AB/SinC = AC/SinB
36.08/Sin58 = 42/SinB
Cross multiplying, it becomes
36.08SinB = 42Sin58
SinB = 42Sin58/36.08 = 0.987
B = Sin^-1(0.987)
B = 81°
Therefore, her bearing from the base camp is
360 - 81 = 279°
Answer:
D) 9
Step-by-step explanation:
8 + 9 + 10 + 7 =39
48 - 39 = 9
Answer:
21.25
Step-by-step explanation:
85÷4=21.25
