Answer:
No
Step-by-step explanation:
Because there are two inputs (-3) and they both lead to two different outputs (2 and 1), it isn't a function
Carter's song played on 7 commercials and 5 movies.
Step-by-step explanation:
Earning per commercial = $50
Earning per movie = $130
Total earned = $1000
Total commercial and movies = 12
Let,
x be the number of commercials
y be the number of movies
According to given statement;
x+y=12 Eqn 1
50x+130y=1000 Eqn 2
From Eqn 1
x=12-y Eqn 3
Putting value of x from Eqn 3 in Eqn 2

Dividing both sides by 80

Putting y=5 in Eqn 1

Carter's song played on 7 commercials and 5 movies.
Keywords: linear equation, substitution method
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Answer: We are 95% confident that the mean SPF level of sunscreen used by all Cal Poly students is between 29.0813 and 40.0187.
Step-by-step explanation:
Given : Significance level : 
Sample size : n= 52 , which is a large sample (n>30), so we use z-test.
By using z-value table,
Critical value: 
Sample mean : 
Standard deviation : 
The confidence interval for population means is given by :-

i.e. 

Now, the 95% confidence interval for the ppopulation mean = . (29.0813, 40.0187)
Hence, We are 95% confident that the mean SPF level of sunscreen used by all Cal Poly students is between 29.0813 and 40.0187.