[Solved] Established Standardizing Mean

our research scenario is off to a good start. It could be improved by specifying the units of measurement for attention span (e.g., measured in seconds) and also the value for the hypothesis. 

Here’s a revised version:

“Is there a significant distinction in the typical attention span (measured in seconds) of children aged 7 to 10, who spend seven to ten years a day in front of a screen, compared to the established standardizing mean of 20 seconds for attention span?

What are some similarities between t-tests and z-scores?