#include <bits/stdc++.h>

using namespace std;

int t, x, y, k;

int main()
{

	scanf("%d", &t);

	while(t--)
	{

		scanf("%d %d %d", &x, &y, &k);

		printf( ( ( ( x * y - 1) == k ) ? "YES\n":"NO\n" ) );

	}

	return 0;

}