#include <bits/stdc++.h>
using namespace std;
typedef signed long long ll;

#define _P(...) (void)printf(__VA_ARGS__)
#define FOR(x,to) for(x=0;x<(to);x++)
#define FORR(x,arr) for(auto& x:arr)
#define FORR2(x,y,arr) for(auto& [x,y]:arr)
#define ALL(a) (a.begin()),(a.end())
#define ZERO(a) memset(a,0,sizeof(a))
#define MINUS(a) memset(a,0xff,sizeof(a))
template<class T> bool chmax(T &a, const T &b) { if(a<b){a=b;return 1;}return 0;}
template<class T> bool chmin(T &a, const T &b) { if(a>b){a=b;return 1;}return 0;}
//-------------------------------------------------------

ll T,A,B,K;
const ll mo=998244353;

ll modpow(ll a, ll n = mo-2) {
	ll r=1;a%=mo;
	while(n) r=r*((n%2)?a:1)%mo,a=a*a%mo,n>>=1;
	return r;
}

void solve() {
	int i,j,k,l,r,x,y; string s;
	
	cin>>T;
	while(T--) {
		cin>>A>>B>>K;
		ll ret=0;
		if(A>=0&&B>=0) {
			if(B==1) ret=A*K%mo;
			else ret=A*modpow(B,K-1)%mo;
		}
		else if(A>=0&&B<0) {
			if(B==-1) {
				ret=A*K%mo;
			}
			else {
				if(K%2==1) {
					ret=A*modpow(-B,K-1)%mo;
				}
				else {
					ret=2*A*modpow(-B,K-2)%mo;
				}
			}
		}
		else if(A<0&&B<0&&K>=2) {
			if(B==-1) {
				ret=(K-1)*(-A)%mo;
			}
			else {
				if(K%2==0) ret=abs(A)*modpow(abs(B),K-1);
				else ret=abs(2*A)*modpow(abs(B),K-2);
			}
		}
		
		
		
		cout<<ret%mo<<endl;
	}
}


int main(int argc,char** argv){
	string s;int i;
	if(argc==1) ios::sync_with_stdio(false), cin.tie(0);
	FOR(i,argc-1) s+=argv[i+1],s+='\n'; FOR(i,s.size()) ungetc(s[s.size()-1-i],stdin);
	cout.tie(0); solve(); return 0;
}