#include<iostream>
#include<cstdio>
#include<cmath>
#include<cstdlib>
#include<cstring>
#include<algorithm>
#include<cassert>
using namespace std;
int read()
{int x=0,f=1;char c=getchar();while (c<'0'||c>'9') {if (c=='-') f=-1;c=getchar();}while (c>='0'&&c<='9') x=(x<<1)+(x<<3)+(c^48),c=getchar();return x*f;
}
#define N 300010
int n,m,q,p[N],deep[N],value[N],ans[N],t=0;
struct base
{int size,a[31];void ins(int x){for (register int i=30;~i;i--){if (!x) break;if (x&(1<<i))if (!a[i]) {a[i]=x;size++;break;}else x^=a[i];}}base operator +(const base&b) const{base c;if (size>b.size){c.size=size;for (int i=0;i<31;i++) c.a[i]=a[i];if (size==31) return c;for (register int i=30;~i;i--)c.ins(b.a[i]);}else{c.size=b.size;for (int i=0;i<31;i++) c.a[i]=b.a[i];if (b.size==31) return c;for (register int i=30;~i;i--)c.ins(a[i]);}return c;}
}pre[N],suf[N];
struct data{int to,nxt,len;
}edge[N<<1];
struct data2{int i,l,r,x;
}Q[N],u[N];
void addedge(int x,int y,int z){t++;edge[t].to=y,edge[t].nxt=p[x],edge[t].len=z,p[x]=t;}
void dfs(int k,int from)
{for (int i=p[k];i;i=edge[i].nxt)if (edge[i].to!=from){deep[edge[i].to]=deep[k]^edge[i].len;dfs(edge[i].to,k);}
}
int work(int x,base p)
{for (int i=30;~i;i--)x=min(x,x^p.a[i]);return x;
}
void solve(int l,int r,int low,int high)
{if (l>r||low>high) return;if (low==high){for (int i=l;i<=r;i++) ans[Q[i].i]=min(Q[i].x,Q[i].x^value[low]);return;}int mid=low+high>>1;for (int i=mid;i>=low;i--){if (i==mid) pre[i]=(base){0,{0}};else pre[i]=pre[i+1];pre[i].ins(value[i]);}for (int i=mid+1;i<=high;i++){if (i==mid+1) suf[i]=(base){0,{0}};else suf[i]=suf[i-1];suf[i].ins(value[i]);}int head=l-1,tail=r+1;for (int i=l;i<=r;i++)if (Q[i].l<=mid&&Q[i].r>mid) ans[Q[i].i]=work(Q[i].x,pre[Q[i].l]+suf[Q[i].r]);else if (Q[i].r<=mid) u[++head]=Q[i];else u[--tail]=Q[i];for (int i=l;i<=r;i++) Q[i]=u[i];solve(l,head,low,mid);solve(tail,r,mid+1,high);
}
int main()
{
#ifndef ONLINE_JUDGEfreopen("c.in","r",stdin);freopen("c.out","w",stdout);const char LL[]="%I64d\n";
#elseconst char LL[]="%lld\n";
#endifn=read(),m=read(),q=read();for (int i=1;i<n;i++){int x=read(),y=read(),z=read();addedge(x,y,z),addedge(y,x,z);}dfs(1,1);for (int i=1;i<=m;i++){int x=read(),y=read(),z=read();value[i]=deep[x]^deep[y]^z;}for (int i=1;i<=q;i++){int s=read(),t=read(),l=read(),r=read();Q[i].i=i,Q[i].x=deep[s]^deep[t],Q[i].l=l,Q[i].r=r;}solve(1,q,1,m);for (int i=1;i<=q;i++) printf("%d\n",ans[i]);return 0;
}