typedef long long ll; #include using namespace std; const int MAX = 510000; const int MOD = 1000000007; long long fac[MAX], finv[MAX], inv[MAX]; // テーブルを作る前処理 void COMinit() { fac[0] = fac[1] = 1; finv[0] = finv[1] = 1; inv[1] = 1; for (int i = 2; i < MAX; i++){ fac[i] = fac[i - 1] * i % MOD; inv[i] = MOD - inv[MOD%i] * (MOD / i) % MOD; finv[i] = finv[i - 1] * inv[i] % MOD; } } // 二項係数計算 long long COM(int n, int k){ if (n < k) return 0; if (n < 0 || k < 0) return 0; return fac[n] * (finv[k] * finv[n - k] % MOD) % MOD; } long long modpow(long long a, long long n) { long long res = 1; while (n > 0) { if (n & 1) res = res * a % MOD; a = a * a % MOD; n >>= 1; } return res; } int main() { cin.tie(0); ios::sync_with_stdio(false); COMinit(); ll n,m,k,p,q; std::cin >> n>>m>>k>>p>>q; ll e,o; e = o = 0; e = modpow(2,MOD-2)*(modpow(1-2*p%MOD*modpow(q,MOD-2)%MOD+MOD,k)+1); e %= MOD; o = 1-e+MOD; o %= MOD; ll ans = 0; vector b(n); for (int i = 0; i < n; i++) { std::cin >> b[i]; ans += ( o*COM(n-1,m)%MOD+ e*COM(n-1,n-m)%MOD )%MOD*b[i]%MOD*modpow(COM(n,m),MOD-2)%MOD; ans %= MOD; // std::cout << ans << std::endl; } std::cout << ans << std::endl; }