Discussion Items:$1.$ Concisely summarize the key differences between SPT and CPT$.$ Include advantages and disadvantages of each penetration testing method$\mathrm{.}2.$ List at least three unconventional subsurface investigation techniques. Briefly explain the principles they work on$.3.$ Search for a geotechnical problem associated with a natural hazard that was assessed using an unconventional site investigation technique $($the tool can be terrestrial, airborne, spaceborne, or offshore$).$ The problem has to have occurred within the last five years. In a few sentences, explain the problem, assessment method, and results.