#include<bits/stdc++.h>
using namespace std;
int t,n;
long long h,zbir;
int main ()
{

    freopen("battle.in","r",stdin);
    freopen("battle.out","w",stdout);
    scanf("%d", &t);
    for(int i=1; i<=t; i++)
    {
        zbir=0;
        scanf("%d%d", &n, &h);   ///n-broj vojnika h-zivot
        for(int j=1; j<=n; j++)
        {
            int l,r;
            scanf("%d%d", &l, &r); ///interval oba ukljucena
            zbir+=(r+l)/2;
        }
        if(zbir>=h)
            printf("YES\n");

        else
            printf("NO\n");
    }

    return 0;
}