1 3 51 
Menu functions provide the user the following 
possibilities:
 1. to set a value for the QCD-lambda6 parameter;
 2. to define the QCD scale. It can be defined as a
constant or as a squared sum of particles momenta.
In the last case digits of the user input correspond 
to particle numbers in the process string. 
For example: user input '13' means Q^2=abs( (p1-p3)^2 );
 3. to display the alpha(s) plot in the region defined
by the user.

  If Q is defined as a constant, the corresponding
value of alpha=GG^2/(4*PI) is displayed under the menu.
