import sys
input = sys.stdin.readline

N, M, K, p, q = map(int, input().split())
B = [int(input()) for _ in range(N)]
MOD = 10**9+7
a = pow(q, K, MOD)
b = pow((q-2*p)%MOD, K, MOD)
c = (a+b)%MOD
d = (a-b)%MOD
e = pow(2*a, MOD-2, MOD)
ans = (c*sum(B[:M])+d*sum(B[M:]))*e%MOD

print(ans)