The owners of a sports stadium want to install electric car charging points in each of the stadium's nine car parks.
An engineer creates a plan which requires installing electrical connections so that each car park is connected, directly or indirectly, to the stadium's main electricity power supply.
The engineer produces the network shown below, where the nodes represent the stadium's main electricity power supply \(X\) and the nine car parks \(A\), \(B\), \(\ldots\), \(I\)
\includegraphics{figure_5}
Each arc represents a possible electrical connection which could be installed.
The weight on each arc represents the time, in hours, it would take to install the electrical connection. The electrical connections can only be installed one at a time.
To reduce disruption, the owners of the sports stadium want the required electrical connections to be installed in the minimum possible total time.
- Determine the electrical connections that should be installed.
[2 marks]
- Find the minimum possible total time needed to install the required electrical connections.
[1 mark]
- Following the installation of the electrical connections, some of the car parks have an indirect connection to the stadium's main electricity power supply.
Give one limitation of this installation.
[1 mark]