#include using std::cin; using std::cout; const char endl = '\n'; const int mod = 200907; int t, a, b, c, k; int binpow(int a, int b) { int res = 1; a %= mod; while (b) { if (b & 1) res = 1ll * res * a % mod; a = 1ll * a * a % mod; b >>= 1; } return res; } int main() { std::ios::sync_with_stdio(false); cin >> t; while (t--) { cin >> a >> b >> c >> k; if (a - b == b - c) { // 等差数列 cout << (a + 1ll * (b - a) * (k - 1)) % mod << endl; } else { // 等比数列 cout << 1ll * a * binpow(b / a, k - 1) % mod << endl; } } return 0; }