#include<bits/stdc++.h>
using namespace std;
#define FOR(i,j,k) for(int i=j;i<=k;++i) 
#define For(i,j,k) for(int i=j;i>=k;--i) 
#define mid ((l+r)>>1)
const int MAX = 1e6 +111;
int cost[MAX],g[MAX],h[MAX];
int a[MAX];
int ok(int M,int n,int k){
	int md = (n+1)>>1;
	int div = 1;
	FOR(i,1,md){
		if(a[i]>M){
			while(a[i]/div>M) ++div;
			k-=h[div];
		}
	}
	return k>=0;
}
signed main(){
	ios::sync_with_stdio(false);
	cin.tie(0);
	cout.tie(0);
//	freopen("1.in","r",stdin);
	int t;
	cin>>t;
	int mx = 1e6;
	while(t--){
		int n,m,k;
		cin>>n>>m>>k;
		FOR(i,1,n) cin>>a[i];
		FOR(i,1,m) cin>>cost[i],g[i] = cost[i];
		sort(a+1,a+1+n);
		FOR(i,1,m){
			FOR(j,1,i){
				if(i*j>m) break;
				g[i*j] = min(g[i*j],g[i]*g[j]);
			}
		}
		int pos = m;
		int cst_min = g[m];
		FOR(i,1,m){
			while(i*(pos-1)>=m) --pos,cst_min = min(cst_min,g[pos]);
			g[m] = min(g[m],g[i]+cst_min);
		}
		h[m] = g[m];
		For(i,m-1,1) h[i] = min(g[i],h[i+1]);
		int l = 0, r = m;
		while(l<r){
			if(ok(mid,n,k)) r = mid;
			else l = mid+1;
		}
		FOR(i,0,m) h[i]=g[i]=cost[i]=0;
		cout<<l<<endl;
	}
	return 0;
}
/*
3
3 5 0
2 5 2
3 2 4 6 13
3 5 3
2 5 3
3 2 4 6 13
3 5 6
2 5 2
3 2 4 6 13
*/