The 1987 explosion at a nuclear lab sent about 1000 kilograms of a radioactive element into the atmosphere. the function f left parenthesis x right parenthesis equals 1000 left parenthesis 0.5 right parenthesis superscript startfraction x over 30 endfraction describes the​ amount, f(x), in​ kilograms, of a radioactive element remaining in the area x years after 1987. if even 100 kilograms of the radioactive element remains in the​ atmosphere, the area is considered unsafe for human habitation. find ​f(80​) and determine if the area will be safe for human habitation by 2067.