Answer:
0.9898 = 98.98% probability that there will not be more than one failure during a particular week.
Step-by-step explanation:
In a Poisson distribution, the probability that X represents the number of successes of a random variable is given by the following formula:

In which
x is the number of sucesses
e = 2.71828 is the Euler number
is the mean in the given interval.
3 failures every twenty weeks
This means that for 1 week, 
Calculate the probability that there will not be more than one failure during a particular week.
Probability of at most one failure, so:

Then



Then

0.9898 = 98.98% probability that there will not be more than one failure during a particular week.
1,600 800+800=1,600 this is your answer
Well to be honest, you need to straight forward to her and tell her that you do not appreciate her copying you and tell her you dont want to be rude or anything, but this needs to stop.
0, because 1/2 = 0.50. therefore .07 is more closer to 0
∠GHJ and ∠RST are complementary
⇒ ∠GHJ and ∠RST = 90°
And ∠RST and ∠ABC are supplementary
⇒ ∠RST and ∠ABC = 180°
Also, ∠GHJ = x°
⇒ ∠RST = 90° - x°
⇒ ∠ABC = 180° - ∠RST
⇒ ∠ABC = 180° - (90° - x°)
⇒ ∠ABC = 90° + x°