Answer: 
Step-by-step explanation:
Given : Sample size : n= 9
Degree of freedom = df =n-1 =8
Sample mean : 
sample standard deviation : 
Significance level ; 
Since population standard deviation is not given , so we use t- test.
Using t-distribution table , we have
Critical value = 
Confidence interval for the population mean :

90% confidence interval for the mean value will be :






Hence, the 90% confidence interval for the mean value= 
4 because when u solve it that’s what you get
a. n-(n - 1) = 1
b. n( n - 1) = n² - n
c. (n - 1) + n = 2n - 1
d. (n - 1) + n = 2n - 1
<h3>Solution:</h3>
General Rule for Equation Solving
- Remove parentheses and combine like terms to simplify each side of the equation.
- To isolate the variable term on one side of the equation, use addition or subtraction.
- To find the variable, use multiplication or division.
Given two consecutive numbers , (n - 1) , n
simplifying :
n - (n - 1)
= n -1(n - 1)
= n - n + 1
= 1
multiplying :
n( n -1)
= n² - n
simplifying :
(n-1) + n
= n - 1 + n
= 2n -1
by adding two numbers :
(n - 1) + n
= n -1 + n
= 2n - 1
To learn more about equations refer to :
brainly.com/question/22688504
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If it is discounted 25%, then u r actually paying 75%
0.75(119) = 89.25 (without tax)
sales tax = 7 1/2% = 7.5% = 0.075
89.25(1.075) = $ 95.94 <===
The answer is D
Type 1 Type 2 plants have somewhat similar height distributions