Suppose  during a laboratory period you were provided with sterile Petri dishes to expose to the environment in the following ways (inoculation):

2. 1. Several coins pressed temporarily on the media
3. 
   
4. 2. Hair combed over exposed petri-dishes
6. 3. Expose the petri-dish by coughing onto it 
8. 4. Swabbing your skin and inoculating the petri-dish with swab

Discuss what you would expect to observe on the Petri dishes (#1-4) after 48hrs of incubation ?  which habitat sampled would you expect to contain more bacteria and why?