$0. She got the $40 ring and then gave it back. 40-40=0.
Answer:
1 hour
Step-by-step explanation:
25min=1 poster for the shop owner
25×4=100
100×8=800
800÷25=32 posters in 8hrs for the shop owner
1hr×8=8 posters for the apprentice
thus 40 in total
The value added to the equation
exists
.
<h3>What is a perfect square?</h3>
A perfect square exists as a number that can be described as the product of an integer by itself or as the second exponent of an integer.
The perfect square trinomial exists
±
=
± 2ab + 


then 
The value of a = x and b = 3



The value added to the equation
exists
.
To learn more about perfect square refer to: brainly.com/question/6946048
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