the ship Earth settler land Mars the colonist manage build n necessary structure surface planet regard plane construction regard point but day scanner record suspicious activity outskirt colony it decide use protective force field generating system protect colony possible troublethe system work follow surface contain number generator field consider point the active range generator circle radius r center location generator boundary circle include range after system activate stretch protective force field surface area generator activity that protect intersection generator active rangesThe number generator available colonist limit system field generation consume lot energy More precisely energy consumption depend number generator directly proportional area protect field also necessary exist building locate protect areadetermine small possible area protect surface contain building