n,m=map(int,input().split())
a=list(map(int,input().split()))
b=list(map(int,input().split()))
dp=[0]*(10**5+1);mod=10**9+7
dp[0]=1
for i in a:
    for j in range(10**5-i,-1,-1):
        dp[j+i]+=dp[j];dp[j+i]%=mod
dp2=[0]*len(dp)
dp2[0]=1
for i in b:
    for j in range(10**5-i,-1,-1):
        dp2[j+i]+=dp2[j];dp2[j+i]%=mod
x,y=map(int,input().split());ans=0
for i in range(len(dp)-1,0,-1):
	dp[i-1]+=dp[i];dp[i-1]%=mod
for i in range(10**5,0,-1):
    if i*x<=10**5:
        ans+=dp[i*x]*dp2[i]%mod
    if i*y+1<=10**5:
        ans-=dp[i*y+1]*dp2[i]%mod
    ans%=mod
print(ans)