A. 18m+45=t
m=months
t=total cost
b.
1 month=$63
6 months = $153
12 months (1 year)= $261
Answer:
0.5466
Step-by-step explanation:
Given that the length of human pregnancies from conception to birth varies according to a distribution that is approximately Normal with mean 266 days and standard deviation 16 days.
Let X be the length of pregnancies
X is N(266,16)
To find out the probability that pregnancies last between 240 and 270 days (roughly between 8 months and 9 months)
P(240<x<270)
convert each into Z score as 
x=240 means Z = -1.625
x=270 means z=0.25
Required prob
= 
1 + 3i, - sqrt 10 would be the other two answers
612/6=102
check: 6x102=612
Hope this helped! :))