Answer: c. z = 1.35; Reject the null hypothesis
Step-by-step explanation:
Let
be the average life expectancy of its batteries.
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.
Test statistic : 
where, n= sample size
= sample mean
= Population mean
=population standard deviation
For
, we have

Critical one-tailed test value for 0.10 significance level :

Decision : Since critical z value (1.28) < test statistic (1.35), so we reject the null hypothesis .
[When critical value is less than the test statistic value , we reject the null hypothesis .]
IN Δ MLN:
∠M = 18.3 , ∠L = 98.6 AND ∠N = 180 - (∠M + ∠L) = 180 - (18.3 + 98.6 ) = 63.1
IN Δ FGH:
∠F = 98.6 , ∠G = 61.1 AND ∠H = 180 - (∠F + ∠G ) = 180 - (98.6 + 61.1 ) = 20.3
∴ ONLY ∠N = ∠F = 98.6
There is no other <span>congruent </span>angles
So, The correct statement is :
Inaccurate. The triangles are not similar because angle M is not congruent to angle H, and angle N is not congruent to angle G.