n,m = map(int,input().split())
vi = [int(i) for i in input().split()]
ri = [int(i) for i in input().split()]
a,b = map(int,input().split())

mod = 10**9+7

dp_vi = [[0 for i in range(sum(vi)+1)] for j in range(n)]
dp_ri = [[0 for i in range(sum(ri)+1)] for j in range(m)]

dp_vi[0][vi[0]] = 1

#print(dp_vi)

for i in range(1,n):
    #print(i)
    for j in range(sum(vi)+1):
        #print(i,j)
        if j-vi[i] > 0:
            dp_vi[i][j] = dp_vi[i-1][j-vi[i]] + dp_vi[i-1][j]
        elif j == vi[i]:
            dp_vi[i][j] = dp_vi[i-1][j] + 1
        else:
            dp_vi[i][j] = dp_vi[i-1][j]

dp_ri[0][ri[0]] = 1

for i in range(1,m):
    #print(i)
    for j in range(sum(ri)+1):
        #print(i,j)
        if j-ri[i] > 0:
            dp_ri[i][j] = dp_ri[i-1][j-ri[i]] + dp_ri[i-1][j]
        elif j == ri[i]:
            dp_ri[i][j] = dp_ri[i-1][j] + 1
        else:
            dp_ri[i][j] = dp_ri[i-1][j]

dp = [0]*(sum(ri)+1)
dp[1] = dp_ri[m-1][1]

for i in range(1,sum(ri)):
    dp[i+1] = dp[i] + dp_ri[m-1][i+1]

ans = 0

#print(dp_ri)
#exit()

for i in range(1,sum(vi)+1):
    #print(i)
    max_ohm = min(i // a,sum(ri))
    #print(st)
    #print(dp[st])
    min_ohm = (i+b-1) // b
    if max_ohm < min_ohm:
        continue
    #print(i,st,ed,dp_vi[n-1][i])
    #print(dp[st],dp[ed-1])
    ans += (dp[max_ohm]-dp[min_ohm-1])*dp_vi[n-1][i]
    ans %= mod

#print(dp_vi)
print(ans)