#include <bits/stdc++.h>
using namespace std;
const long long M = 1000000007;
long long pw(long long a, long long b) {
    long long r = 1;
    while (b) {
        if (b & 1) r = r * a % M;
        a = a * a % M;
        b >>= 1;
    }
    return r;
}
long long fc(long long n) {
    if (n <= 1000000) {
        long long r = 1;
        for (long long i = 2; i <= n; i++) r = r * i % M;
        return r;
    }
    if (n > M / 2) {
        long long r = 1;
        for (long long i = n + 1; i < M; i++) r = r * i % M;
        return (M - 1) * pw(r, M - 2) % M;
    } else {
        long long r = 1;
        for (long long i = 2; i <= n; i++) r = r * i % M;
        return r;
    }
}
int main() {
    ios::sync_with_stdio(0);
    cin.tie(0);
    int T;
    cin >> T;
    while (T--) {
        string sC, sP;
        cin >> sC >> sP;
        bool big = false;
        if (sP.size() > 10) big = true;
        else if (sP.size() == 10 && sP >= "1000000007") big = true;
        if (big) {
            cout << 0 << "\n";
            continue;
        }
        long long p = 0;
        for (char ch : sP) p = p * 10 + (ch - '0');
        long long cm = 0;
        for (char ch : sC) cm = (cm * 10 + (ch - '0')) % M;
        bool ok = true;
        if (sC.size() > 10) ok = true;
        else {
            long long c = 0;
            for (char ch : sC) c = c * 10 + (ch - '0');
            if (c < 2 * p - 1) ok = false;
        }
        if (!ok) {
            cout << 0 << "\n";
            continue;
        }
        long long r = (cm - p + 1) % M;
        if (r < 0) r += M;
        if (r < p - 1) {
            cout << 0 << "\n";
            continue;
        }
        long long ans;
        if (p <= 1000000) {
            ans = 1;
            for (long long i = 0; i < p; i++) {
                long long x = r - i;
                if (x < 0) x += M;
                ans = ans * x % M;
            }
        } else {
            long long a = fc(r);
            long long b = fc(r - p);
            ans = a * pw(b, M - 2) % M;
        }
        cout << ans << "\n";
    }
    return 0;
}