Answer:
  export               import                net export  
1. increases         unchanged         increases
2. unchanged       increases             decreases
3.  unchanged       increases             decreases
4. unchanged       increases             decreases
5. increases         unchanged         increases 
Explanation:
export would comprise of goods and services produced in the US that are been sold to foreign countries
Import would comprise of foreign produced goods and services that are been sold in the US
Net export would increase when export occurs and decrease when import occurs
Net export = exports – imports
When the French historian visits the US museum and the European family visits Disney,  they are enjoying US services, thus export increases and net export increases
The purchase of books from Cambridge in UK, Panasonic camera and the visit to Japan constitutes import. These increases import and reduces net export