//It's MyGO!!!
//All OK
#include <bits/stdc++.h>
#define ios ios::sync_with_stdio(0);cin.tie(nullptr);cout.tie(0);cout << fixed << setprecision(6)
#define fi first
#define se second
#define INF 0x3f3f3f3f
#define LNF (1ll << 60)
#define ll long long
#define ull unsighed long long
// #define int long long
// #define mod 998244353
#define mod 1000000007
using namespace std;

const int N = 1e6 + 10;
int n, m, k;
int idx;
int vis[N];
ll a[N], cost[N];

void init(){

}

int cal(int num, int x){
    int y = ceil(num / x);
    return y;
}

int check(int x){
    ll sum = 0;
    // cout << x << endl;
    for(int i = 1; i <= n; i ++){
        idx = i;
        if(a[i] >= x)
            break;
    }

    if(idx > n / 2 + 1)
        return 1;
    // cout << idx << ' ' << sum << endl;
    for(int i = idx + 1, num = 1; num + idx <= n / 2 + 1; i ++, num ++){
        // cout << i << ' ' << num << ' ' << num + idx << ' ' << cal(a[i], x) << ' ' << cost[cal(a[i], x)] << endl;
        int y = cal(a[i], x);
        if(y == 1)
            continue;
        else
            sum += cost[y];
    }
    // cout << idx << ' ' << sum << ' ' << k << endl;
    return sum <= k;
}

void solve(){
    cin >> n >> m >> k;
    for(int i = 1; i <= n; i++)
        cin >> a[i];
    memset(cost, 0x3f, sizeof cost);

    for(int i = 1; i <= m; i ++){
        int x; cin >> x;
        if(i == 1)
            cost[i] = x;
        else{
            ll cnt = i, sum = x;
            while(cnt <= m){
                cost[cnt] = min(cost[cnt], sum);
                sum += x;
                cnt *= cnt;
            }
            cost[m + 1] = min(cost[m + 1], sum);
        }
    }
    for(int i = m; i >= 1; i --)
        cost[i] = min(cost[i], cost[i + 1]);

    sort(a + 1, a + 1 + n);
    // for(int i = 1; i <= n; i ++)
    //     cout << a[i] << ' ';
    // cout << '\n';
    // for(int i = 1; i <= m; i ++)
    //     cout << cost[i] << ' ';
    // cout << '\n';
    

    
    int l = 1, r = m, ans;
    while(l <= r){
        int mid = l + r >> 1;
        // cout << l << ' ' << r << ' ' << ans << ' ' << mid << endl;
        if(check(mid))
            ans = mid, r = mid - 1;
        else l = mid + 1;
    }
    cout << ans << '\n';
    // cout << '\n';
}

signed main(){
    ios;

    // init();
    int _ = 1;
    cin >> _;
    for(int __ = 1; __ <= _; __ ++){
        // cout << "Case #" << __ << ": ";

        solve();
    }
    return 0;
}