Myrtle has a credit card that uses the average daily balance method. for the first 21 days of one of her billing cycles, her balance was $2030, and for the last 9 days of the billing cycle, her balance was $1450. if her credit card's apr is 23%, which of these expressions could be used to calculate the amount myrtle was charged in interest for the billing cycle?
(a)- (0.23/365 x30)÷(21x $2030+ 9x$1450/30)
(b)- (0.23/365 x30)÷(9x $2030+ 21x$1450/30)
(c)- (0.23/365 x31)÷(9x $2030+ 21x$1450/31)
(d)- (0.23/365 x31)÷(21x $2030+ 9x$1450/31)

There is no sufficient evidence to suggest that the relaxation exercise slowed the brain waves

Step-by-step explanation:

Given that in a  experiment on relaxation techniques, subject's brain signals were measured before and after the relaxation exercises with the following results:

The population is normally distributed

This is a paired t test since sample size is very small and same population under two different conditions studied.

(Right tailed test)

Alpha = 5%

xyDiff

32266

38362

66597

4952-3

29245

Mean3.4

Std dev4.037325848

Mean difference =

n =5

Std deviation for difference =

Test statistic t = mean difference / std dev for difference

=

p value =0.132

Since p >0.05 we accept null hypothesis.

There is no sufficient evidence to suggest that the relaxation exercise slowed the brain waves