Answer:
i know it breaks your heart move to a city in a broke down car
Answer:

Step-by-step explanation:
Given
-- total
--- defective
--- selected
Required
The probability of rejecting the batch
This means that at least one of the selected piece is defected.
So, we first calculate the probability that all the selected piece are accepted.
So, we have:

The denominator decreases by 1 because it is a probability without replacement; 180 is subtracted from the numerator to represent the number of non-defective CDs
So, we have:


Using the complement rule, the probability that the batch will be rejected is:


1 time=2mins
xtimes=30mins
30/2 ×1= 15.
Therefore it can be completed 15 times in 30mins
Answer is B
-0.6- (-0.4)= -0.6+0.4= -0.2