/**************************************************************

    Problem:

    User: BLADEVIL

    Language: Pascal

    Result: Accepted

    Time: ms

    Memory: kb

****************************************************************/

 

//By BLADEVIL

 

var

 

    n, m, t2, v                     :longint;

 

    t1                              :real;

 

    dis                             :array[..,..] of real;

 

    ans                             :real;

 

    pre, other, last                :array[..] of longint;

 

    link                            :array[..] of longint;

 

    flag                            :array[..] of boolean;

 

    x1, x2, y1, y2                  :array[..] of longint;

 

    l                               :longint;

 

    len                             :array[..] of real;

 

  

 

procedure init;

 

var

 

    i, j                            :longint;

 

begin

 

    read(n,m,t1,t2,v);

 

    for i:= to m do read(x2[i],y2[i]);

 

    for i:= to n do read(x1[i],y1[i]);

 

    t1:=t1/;

 

    for i:= to n do

 

        for j:= to m do

 

            dis[i,j]:=sqrt((x1[i]-x2[j])*(x1[i]-x2[j])+(y1[i]-y2[j])*(y1[i]-y2[j]));

 

end;

 

  

 

procedure connect(x,y:longint; z:real);

 

begin

 

    inc(l);

 

    pre[l]:=last[x];

 

    last[x]:=l;

 

    other[l]:=y;

 

    len[l]:=z;

 

end;

 

  

 

function find(i:longint):boolean;

 

var

 

    q, p                            :longint;

 

begin

 

    q:=last[i];

 

    while q<> do

 

    begin

 

        p:=other[q];

 

        if (not flag[p]) then

 

        begin

 

            flag[p]:=true;

 

            if (link[p]=) or (find(link[p])) then

 

            begin

 

                link[p]:=i;

 

                exit(true);

 

            end;

 

        end;

 

        q:=pre[q];

 

    end;

 

    exit(false);

 

end;

 

  

 

procedure judge(low,high:real);

 

var

 

    mid                             :real;

 

    tot                             :longint;

 

    i, j, ll                        :longint;

 

    k                               :longint;

 

    count                           :longint;

 

begin

 

    if high<low then exit;

 

    fillchar(last,sizeof(last),);

 

    fillchar(link,sizeof(link),);

 

    tot:=;

 

    l:=;

 

    mid:=(low+high)/;

 

    k:=trunc(((mid-t1)/(t1+t2))+);

 

    for i:= to n do

 

        for ll:= to k do

 

        begin

 

            inc(tot);

 

            for j:= to m do

 

                if (((mid-t1)-(ll-)*(t1+t2))*v)>=dis[i,j]

 

                    then connect(tot,j,dis[i,j]/v+(ll-)*(t1+t2)+t1);

 

        end;

 

    count:=;

 

  

 

    for i:= to tot do

 

    begin

 

        fillchar(flag,sizeof(flag),false);

 

        if find(i) then inc(count);

 

    end;

 

  

 

    if (high-low<1e-8) then

 

        if count>=m then

 

        begin

 

            ans:=mid;

 

        end else exit;

 

    if count>=m then

 

    begin

 

        ans:=mid;

 

        judge(low,mid-1e-8);

 

    end else judge(mid+1e-8,high);

 

end;

 

  

 

procedure main;

 

begin

 

    judge(,);

 

    writeln(ans::);

 

end;

 

  

 

begin

 

    init;

 

    main;

 

end.