Answer:
mu = the population true mean time spent by teenagers playing computer game this year
Step-by-step explanation:
Dear student, there is no much information given to answer this question but we will try as much as possible to explain (what is the parameter) of the true mean.
In 1990s;
μ = 10.2 hours/week
From the information given,we understand that the parameter is linked to the population, and we're looking for the population average time spent playing computer games by teens in the current situation.
In this situation, the population parameter is the population true mean mu = the population true mean.