I believe that the question is referring to what is called a Pace Car which generally pulls in front of the pack of cars to control the speed and position of the following vehicles.
A group of leaves is called a pile. A pile of leaves is collected together during the autumn season when they fall from the trees.
You take a bunch of dog racing tubes and put them together.
bunch
WHAT IS A GROUP OF ATHLETES CALLED
A group of grapes is called a bunch of grapes.
A bunch of penguins are called a flock of penguins.
During cell division the structures that the DNA of eukaryotes bunch into are the chromosomes.chromosomes
During cell division the structures that the DNA of eukaryotes bunch into are the chromosomes.chromosomes
During the so-called Dark Ages, Spain was a bunch of independent kingdoms (countries) each with its own name. Some of them included:CastillaLeonEstremaduraNavarreValenciaAragon
a stem of orchids is called a spray but multiple sprays would be called a bunch
The man fed a bunch of pigeons in the park, during his lunch break.
A bunch of tigers Is called an Ambush or Streak.