The decision tree $($hierarchy$)$ below was constructed to help decide which, among several types of computers, should be purchased. The weights were decided upon by the prospective buyer who was looking for a new computer. Note that all the criteria are objective and can easily be quantified except reliability which has been rated by an expert on a scale from $1$ to $10,$ with $1$ being very reliable and $10$ being very unreliable.

The following table gives the ratings of each alternative computer with respect to the above criteria.

Computer

Reliability

Price

Processor Speed

RAM