n,m = map(int,input().split())
V = list(map(int,input().split()))
R = list(map(int,input().split()))
a,b = map(int,input().split())
mod = 10**9+7

M = 10**5+5
dpV = [0]*M
dpR = [0]*M
dpV[0] = 1
dpR[0] = 1

for v in V:
    for i in range(M)[::-1]:
        if dpV[i] == 0:
            continue
        dpV[i+v] += dpV[i]
        dpV[i+v] %= mod
    
for r in R:
    for i in range(M)[::-1]:
        if dpR[i] == 0:
            continue
        dpR[i+r] += dpR[i]
        dpR[i+r] %= mod

cumR = [0]*M
for i in range(M):
    cumR[i] = cumR[i-1]+dpR[i]
    cumR[i] %= mod

ans = 0
for i in range(1,M):
    if dpV[i] == 0:
        continue
    r = i//a
    l = (i+b-1)//b

    if r == 0:
        continue
    count = cumR[r]-cumR[max(l-1,0)]

    ans += dpV[i]*count%mod
    ans %= mod
print(ans)