Task.Run(() => - order of processing ......multithreading in foreach loop?

Hi, I have a question about the order of the code is processed in multi threaded envrioment


I have a bunch of cars with tracking data
I need to look at each cars tracking record (ordered by datetime) and do some stuff (it HAS to be processed in datetime order - one at a time)

This was way to slow, so now i've made the app multithreaded,
I've essentially got
GROUPS - (each item in group is 1 car)
POSITIONS - (all the cars positions data in right order)

i.e.
GROUPS
--Car 1
-----All Car 1 Positions

--Car 2
-----All Car 2 Positions

etc

In my code I have this working, but i'm not sure if they will be processed as I want
i.e. I need car 1 and car 2 etc to be processed at same time of different threads, but their POSITION data to be processed 1 at a time in right order
consider the following code

foreach (var car in GroupOfCarsAndPositions.ToList())
{

                    Task.Run(() =>
                    {
                       //each car should be processed at the same time (multithreaded)

                        foreach (var position in car.PositionsList.ToList())
                        {
                              //each position  Item in this group should be processed one at a time
                         }
                     }
}

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my question is, will the first foreach be processed multithreaded? (i.e. each car be processed at same time?)