complex environment complex environmental complex environments complex equation complex equations complex equipment complex events complex example complex exercise complex expression complex factors complex family complex features complex field complex figure complex financial complex fire complex fluids complex food complex form complex formation complex formed complex forms complex function complex functions complex game complex genetic complex geometric complex geometries complex geometry complex global complex group complex had complex has complex have complex having complex health complex heart complex history complex houses complex human complex humanitarian complex idea complex ideas complex images complex in nature complex in terms complex in the world complex includes complex individual complex industrial complex industry complex information complex infrastructure complex installation complex instruments complex integrated complex integration complex interaction complex interactions complex internal complex international complex interplay complex interventions complex investigations complex is composed complex is formed complex is known complex is located complex is made complex is not complex is used complex issue complex issues complex it complex jobs complex known complex language complex learning complex legal complex legal issues complex lies complex life complex life cycle complex litigation complex located complex logic complex logistics complex machine complex machines complex made complex magazine complex man complex management complex manifold complex manner complex manufacturing complex market complex material