Answer:
a) There is no significant difference between restaurants with and without order-confirmation boards
b) -12.5 ± 3.604 or C.1.E (-16.10, -8.90)
Step-by-step explanation:
answers are in the attachment below
53x2=106
250-106= 144
144/2=72
The length is 72cm
To round off to 10, the difference should range from 5 to 14. If the difference between two numbers is from 5 to 14, they all are rounded to 10.
Example:
(near to 10)



Add 4 to both sides
w = -6