what is a Monocoque structure?

Monocoque structure consists of framework of

external skin with little internal framework

What is a truss type structure? 

Truss type structure is all internal

       Are Compression and tension primary stresses or secondary stresses?

primary stresses

 
       what is the length wise structural support of a wing?

Spar 

what gives the wing its airfoil shape?

The ribs 

which metal has low strength?

      Aluminum

  Which metal has a high cost?

Titanium

what can be done to

helps protect aluminum alloys?

Cladding and paint

What does strength mean? 

The ability to withstand stress. 

what does strain mean? 

The amount of stress per extention