Final answer:
In Saskatchewan, child safety restraints must be used according to age and size, with guidelines recommending restraints up to at least age 6, transitioning to seat belts when appropriate. There isn't a specific answer like 'until the age of 8' or regardless of age and size. Information on the unsupervised time of children in Saskatchewan requires local data, which is not provided.
Step-by-step explanation:
In Saskatchewan, child safety restraints must be used according to specific age and size guidelines to ensure the safety of children. While there isn't a clear cut-off such as age 5, 8, or 12, it is recommended that children use appropriate restraints and booster seats until they are tall enough to properly use a seat belt. The guidance generally includes infants and toddlers up to at least age 6 in age-specific restraints, with variations depending on their size and particular car seats' instructions. The requirement is not regardless of age and size, as older children can transition into using regular seat belts when appropriate.
As for the unsupervised time, without specific data provided for Saskatchewan, it's not possible to accurately answer what percentage of children spend more than 10 hours per day unsupervised or the amount of time 70 percent of the children spend unsupervised. For such statistics, one would need to refer to local surveys or studies conducted within the community.