#include <bits/stdc++.h>

using namespace std;

using ll = long long;

constexpr char newl = '\n';

constexpr ll MOD = 1000000007;

ll modpow(ll x, ll n, ll mod = MOD) {
    ll res = 1;
    while (n > 0) {
        if (n & 1) res = res * x % mod;
        x = x * x % mod;
        n >>= 1;
    }
    return res;
}

// y * y >= x を満たす最小の整数yを求める
ll calcSquare(ll x) {
    ll ng = 0, ok = x;
    while (ok - ng > 1) {
        ll mid = (ng + ok) / 2;
        (mid * mid >= x ? ok : ng) = mid;
    }
    return ok;
}

struct custom_hash {
    static uint64_t splitmix64(uint64_t x) {
        // http://xorshift.di.unimi.it/splitmix64.c
        x += 0x9e3779b97f4a7c15;
        x = (x ^ (x >> 30)) * 0xbf58476d1ce4e5b9;
        x = (x ^ (x >> 27)) * 0x94d049bb133111eb;
        return x ^ (x >> 31);
    }

    size_t operator()(uint64_t x) const {
        static const uint64_t FIXED_RANDOM = chrono::steady_clock::now().time_since_epoch().count();
        return splitmix64(x + FIXED_RANDOM);
    }
};

// g^x == y (mod p) の解xを求める（なければ-1を返す）
constexpr ll p = MOD;
ll modlog(ll g, ll y) {
    g %= p;
    y %= p;

    if (g == 1 && y != 1) return -1;
    if (y == 1) return 0;

    ll sq = calcSquare(p);

    unordered_map<ll, ll, custom_hash> baby_table;
    for (ll i = 0, b = 1; i < sq; i++) {
        baby_table[b] = i;
        (b *= g) %= p;
    }

    ll inv_gsq = modpow(modpow(g, p - 2, p), sq, p);

    for (ll i = 0; i < sq; i++) {
        if (baby_table.find(y) != baby_table.end()) {
            return i * sq + baby_table[y];
        }
        (y *= inv_gsq) %= p;
    }
    return -1;
}

int main() {
    cin.tie(nullptr);
    ios::sync_with_stdio(false);

    constexpr ll g = 5;

    int t;
    cin >> t;
    for (int i = 0; i < t; i++) {
        ll x, K;
        cin >> x >> K;
        if (x == 0) {
            cout << 0 << newl;
            continue;
        }
        ll y = modlog(modpow(g, K), x);
        assert(y >= 0);
        y %= (MOD - 1);
        ll ans = modpow(g, y);
        cout << ans << newl;
    }

    return 0;
}