//doing a 800 difficulty question using dynammic programming
#include<bits/stdc++.h>
#define ll long long
using namespace std;
int main(){
    int t;
    cin>>t;
    while(t--){
        ll n,m,k;
        cin>>n>>m>>k;
        ll dp[n][m];
        for(ll i=0;i<n;i++){
            for(ll j=0;j<m;j++){
                if(i==0){
                    dp[i][j]=j;
                }
                if(i!=0){
                    dp[i][j]=dp[i-1][j]+(j+1);
                }}}
                if(dp[n-1][m-1]==k){
                    cout<<"YES"<<"\n";
                }
                else{
                    cout<<"NO"<<"\n";
                }
        }}