Answer:
d. The population standard deviation is known.
Step-by-step explanation:
T-distribution or Z-distribution, which to use?
If we have the population standard deviation is known, we use the z-distribution.
Otherwise, if we only have the standard deviation for the sample, we use the t-distribution.
Which of the following is not appropriate to use the t-confidence interval for
When the population standard deviation is known, so letter d.
Answer:
Step-by-step explanation:


Volume = 
find partial derivatives using product rule

i.e.
Using maximum for partial derivatives, we equate first partial derivative to 0.
y=0 or x+y =6
x=0 or x+4y =12
Simplify to get y =2, x = 4
thus critical points are (4,2) (6,0) (0,3)
Of these D the II derivative test gives
D<0 only for (4,2)
Hence maximum volume is when x=4, y=2, z= 4/3
Max volume is = 4(2)(4/3) = 32/3
33/50 because it is biggest
Answer:
$240
Step-by-step explanation:
Fill in the given numbers and do the arithmetic.

Keri's monthly loan payment is $240 per month.