Answer:
Step-by-step explanation:
Given that the random variable X is normally distributed, with
mean = 50 and standard deviation = 7.
Then we have z= 
Using this and normal table we find that
a) 
b) When z=0.02
we get

c) 90th percentile z value =1.645
90th percentile of X 
first
second
and fifth are true
Basically the square root of -1 is i. From that you should be able to deduce the answers.
Answer:
D. 6, 7
Step-by-step explanation:
12 - x < 7
-x < -5
(whenever you multiply or divide an inequality by a negative you must switch the inequality symbol)
x > 5
Answer:
It would be 80 miles in 1 hour
Step-by-step explanation:
You divide 560/7
7 goes into 56, 8 times and into 0, 0 times.
560/7=80