Question 9 gives guidance as to what's needed. Post a pic of the symbol you have created (or which LTS auto-generated) for the relay, and of a schematic showing the components specified.

 

i would sue the compiler of the exercise -- for wasting my time -- asking me to do something that can't be done

• ... " For this use the behavioral sources in such a way
  that when the current in the coil of the relay
  exceeds the certain threshold . . .
  . . . we have a contact of the pin COM with the pin T " ...
  .
• you can set a resistor.. (used as a variable resistance pass element e.g. a switch) ..value as
  R = 1G*u(20m-abs(I(L1)))+2m
  // e.g. if the amplitude value of the current is greater than 20m the "Step Function" u() returns 0
  // and the R will thus equal 2mΩ . . . otherwise the u() returns 1 and the R = (1G+2m)·1Ω
  .
• or -- you can use a voltage or current controlled switch
  .
  
• but you cannot make an Ohm'ic (e.g. a resistive) connection to COM with behavioral I or V source only