Answer: D) 
Step-by-step explanation:
As per given , we have
Sample size : n= 15
sample mean : 
Sample standard deviation: s= $20
Since population standard deviation is unknown , so we use t-test.
Significance level for 95% confidence : 
Critical t-value :
[Using students' t-value table]
Required 95% Confidence interval :-

Hence, the required 95% confidence interval for the mean amount its credit card customers spent on their first visit to the chain's new store in the mall assuming that the amount spent follows a normal distribution.:

Answer:
B. A(r(t)) = 25πt²
Step-by-step explanation:
Find the completed question below
The radius of a circular pond is increasing at a constant rate, which can be modeled by the function r(t) = 5t where t is time in months. The area of the pond is modeled by the function A(r) = πr². The area of the pond with respect to time can be modeled by the composition . Which function represents the area with respect to time? A. B. C. D.
Given
A(t) = πr²
r(t) = 5t
We are to evaluate the composite expression A(r(t))
A(r(t)) = A(5t)
To get A(5t), we will replace r in A(t) with 5t and simplify as shown
A(5t) = π(5t)²
A(5t) = π(25t²)
A(5t) = 25πt²
A(r(t)) = 25πt²
Hence the composite expression A(r(t)) is 25πt²
Option B is correct.
To factor completely 18b - 32, we factor out the common factor of the two terms and divide each of term by the common factor.
18b - 32 = 2(18b/2 - 32/2) = 2(9b - 16)
Answer: C
Step-by-step explanation:
48/64=3/4
a^(4-2)x b^(3-2)x c^(1-2)=a^2xb/c
Answer:
Step-by-step explanation:
She'll make a total of 0.20 cents more so she'll make 6.45 per hour
thank you
And may I please be rewarded with brainliest I only need one more to go up in ranking