During your lunchtime in school, you decided to go out and went 70 m south to a coffee shop, and ordered your favourite coffee. Then you walked 40 m due north to a park, where you sat and enjoyed your coffee. It took you 55.0 s to walk from the school to the coffee shop and then 72.0 s to walk from the coffee shop to the park. Determine your average velocity and average speed for the duration of your lunch break. Consider the motion in the south direction to be positive.

At t₁ = 1.5 s, an object is situated at a position x₁ = 12.3 m, and at t₂ = 7.8 s, it's found at x₂ = 25.6 m. i) Determine the object's average velocity throughout this time span. ii) Is it possible to ascertain its average speed based on these data? Provide an explanation for your answer.

A car accelerates from rest and covers a distance of 120 m in 15s. It then turns and travels halfway back in 4.0 s. Calculate the car's average speed during the entire journey.

Consider a train that initially travels 1.50 × 10³ miles at a speed of 180 mph. It then reduces its speed to 120 mph for the subsequent 3.00 × 10³ miles. Determine i) the journey's total duration and ii) the train's average speed (in mph) for the entire trip.

Brian starts in his car from his house at 8.20 a.m., moves at a constant speed towards the east for 2 minutes, takes a U-turn at 400 m and drives at the same constant speed towards the supermarket which is 1500 m from the U-turn. He reached the supermarket at 8.30 a.m. Determine the average velocity of Brian's car for the whole trip.