90
-12. The newsstand had 90 copies at the beginning of the day
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78
For this case we must find the domain of the following function:

By definition, the domain of a function is given by all the values for which the function is defined.
In this case, the argument of the expression must be greater than 0 to be defined.

Thus, the domain of the function is given by all the values of x greater than -2.
Answer:
Domain: 
Answer:
3:6:9
Step-by-step explanation:
1/1+2+3 × 90 = 15
2/1+2+3 × 90 = 30
3/1+2+3 × 90 = 45
5/6(3/2) = 15/12
5/4
1 and 1/4 hours