program n_17;

var E,g,h,m:real;

begin

writeln ('Ввести E,g,h');

readln(E,g,h);

m:=E/(g*h);

writeln('m=',m:8:2);

END.

program n_18;

var R,R1,R2,R3,R4:real;

begin

writeln ('Ввести R1,R2,R3,R4');

readln(R1,R2,R3,R4);

R:=(R1*R2*R3*R4)/(R1+R2+R3+R4);

writeln('