#include<bits/stdc++.h>
#define ll long long
#define all(a) (a).begin(),(a).end()
using namespace std;

#define int ll
const int N = 1e6 + 10;

int n, m, k;
int a[N], cost[N];

int mi[21][N], Log[N];
void init_ST()
{
    for(int i = 1; i <= m + 1; i++) mi[0][i] = cost[i];
	for (int j = 1; j <= 20; j++)
		for (int i = 1; i + (1 << j) - 1 <= m + 1; i++)
			mi[j][i] = min(mi[j - 1][i], mi[j - 1][i + (1 << (j - 1))]);
	Log[1] = 0;
	for (int i = 2; i <= m + 1; i++) Log[i] = Log[i / 2] + 1;
}
int query(int l, int r)
{
	int k = Log[r - l + 1];
	return min(mi[k][l], mi[k][r - (1 << k) + 1]);
}

bool check(int x)
{
    int res = 0;
    for(int i = 1; i <= n / 2 + 1; i++) 
    {
        if(a[i] > x)
        {
            int L = (a[i] + 1 + x) / (x + 1);
            if(x == 0) L = a[i] + 1;
            int R = m + 1;
            res += query(L, R);
        }

        if(res > k) return 0;
    }
    return 1;
}

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

    sort(a + 1, a + 1 + n);

    cost[m + 1] = 1e18;
    for(int i = 1; i <= m + 1; ++i){
		for(int j = 1; i * j <= m + 1 && j <= m; ++j){
			cost[i * j] = min(cost[i * j], cost[i] + cost[j]);
		}
	}
    // cost[m + 1] = cost[m + 2] = cost[m + 3] = 1e18;
    // m += 2;
    // for(int i = 2; i <= m + 1; i++)
    //     for(int j = 2; j * j <= i; j++)
    //         if(i % j == 0) cost[i] = min(cost[i], cost[j] + cost[i / j]);

    init_ST();

    int l = 0, r = a[n / 2 + 1];
    int ans = r;
    while(l <= r)
    {
        int mid = (l + r) / 2;
        if(check(mid)) r = mid - 1, ans = mid;
        else l = mid + 1;
    }

    ++tot;
    cout << ans << '\n';
}

signed main()
{
    ios::sync_with_stdio(false);
    cin.tie(nullptr);cout.tie(nullptr);
    
    // init();

    int t = 1;
    cin >> t;
    while(t--) solve();
    return 0;
}