Answer:
Correct option: B. 90%
Explanation:
The confidence interval is given by:
![CI = [\bar{x} - z\sigma_{\bar{x}} , \bar{x}+z\sigma_{\bar{x}} ]](https://tex.z-dn.net/?f=CI%20%3D%20%5B%5Cbar%7Bx%7D%20-%20z%5Csigma_%7B%5Cbar%7Bx%7D%7D%20%2C%20%5Cbar%7Bx%7D%2Bz%5Csigma_%7B%5Cbar%7Bx%7D%7D%20%5D)
If
is 190, we can find the value of
:



Now we need to find the value of
:


So the value of z is 1.71.
Looking at the z-table, the z value that gives a z-score of 1.71 is 0.0436
This value will occur in both sides of the normal curve, so the confidence level is:

The nearest CI in the options is 90%, so the correct option is B.
Answer:
Total BF for the interior wall is 7.50BD
Explanation:
Given Data:
· Size of stud = 2” x 6”
· Height of Wall = 8 ft
· Top plates = 2
· Bottom Plate = 1
BF stands for board feet in lumber/wood terminology. It is the unit of volume.
1 BF (Board feet) = 1 ft x 1 ft x 1 inch
Since there are total three plates at top and bottom, we have to deduct their thickness from wall height to calculate height of stud.
Height of stud = 8’ – 3 x 2” = 7’6” = 7.5 ft
Board feet of one stud = 7.50 6/12 x 2 = 7.50 BD
Total BF for the interior wall is 7.50BD
Answer:
Time =t2=58.4 h
Explanation:
Since temperature is the same hence using condition
x^2/Dt=constant
where t is the time as temperature so D also remains constant
hence
x^2/t=constant
2.3^2/11=5.3^2/t2
time=t^2=58.4 h
Answer:
no of unit is 17941
Explanation:
given data
fixed cost = $338,000
variable cost = $143 per unit
fixed cost = $1,244,000
variable cost = $92.50 per unit
solution
we consider here no of unit is = n
so here total cost of labor will be sum of fix and variable cost i.e
total cost of labor = $33800 + $143 n ..........1
and
total cost of capital intensive = $1,244,000 + $92.5 n ..........2
so here in both we prefer cost of capital if cost of capital intensive less than cost of labor
$1,244,000 + $92.5 n < $33800 + $143 n
solve we get
n > 
n > 17941
and
cost of producing less than selling cost so here
$1,244,000 + $92.5 n < 197 n
solve it we get
n >
n > 11904
so in both we get greatest no is 17941
so no of unit is 17941