After 100 more minutes, the rate has gone from 30 to 80, increasing by 50. 100 divided by 50 is 2 so for every 2 minutes she is charged one dollar, but per minute the rate is 50 cents per minute. Hope this helps :)
Answer:

Step-by-step explanation:
Given

= 
=
×
← cancel (x + 50)(x + 1) on numerator/denominator
= 
Answer:
27.1
Step-by-step explanation:
Given:
mean=25
standard deviation=4
z0.70=0.525

z*sd = x-mean= 2.1
the lowest score for the top 30%: x=27.1
Answer:
3
Step-by-step explanation:
absolute values can never be negative.
Answer:
50
Step-by-step explanation:
5(-2)^2 + 3(10)
5(4) + 30
20 + 30
50
Hope this helped :D