import numpy as np

N, M = map(int, input().split())
V = tuple(map(int, input().split()))
R = tuple(map(int, input().split()))
A, B = map(int, input().split())

MOD = 10 ** 9 + 7
MAX = 10 ** 5 + 1
dpv = np.zeros(MAX, dtype=np.int64)
dpv[0] = 1
for i in range(N):
    dpv[V[i]:] += dpv[:-V[i]]
    dpv %= MOD

dpr = np.zeros(MAX, dtype=np.int64)
dpr[0] = 1
for i in range(M):
    dpr[R[i]:] += dpr[:-R[i]]
    dpr %= MOD

v_sum = [0] * MAX
for i in range(MAX - 1):
    v_sum[i + 1] = (v_sum[i] + dpv[i]) % MOD

ans = 0
for i in range(1, MAX):
    l, r = A * i, min(MAX - 1, B * i + 1)
    if l >= MAX:
        break
    ans = (ans + (v_sum[r] - v_sum[l]) * dpr[i]) % MOD
print(ans)