Answer:
We need at least 217 compact fluorescent light bulbs
Step-by-step explanation:
We have that to find our 
level, that is the subtraction of 1 by the confidence interval divided by 2. So:
Now, we have to find z in the Ztable as such z has a pvalue of 
.
So it is z with a pvalue of 
, so 
Now, find M as such
In which 
is the standard deviation of the population and n is the size of the sample.
How many compact fluorescent light bulbs need to be selected?
We need at least n bulbs, in which n is found when 
So
We need at least 217 compact fluorescent light bulbs
Answer:
$8d
Step-by-step explanation:
cost of each CD = $8
number of CD's = d
total cost = number of CD's x cost of each CD
= d x $8
= $8d
Answer:
Step-by-step explanation: 0.2 seconds
Answer:
Two angles are called complementary when their measures add to 90 degrees. ∠1 is 60 degrees ∠2 is 30 degrees so if you add it up, the answer is 90 degrees.
∠4 + ∠3 = answer has to be 90 degrees to call it a complementary angle
30 degrees + 60 degrees = 90 degrees
