p1,p2,q1,q2,T=map(int,input().split())
M=998244353
P=p1*pow(p2,M-2,M)%M
Q=q1*pow(q2,M-2,M)%M
q=[0]*(T+1)
q[0]=1
for i in range(1,T+1):
  for j in range(i):
    q[i]+=q[j]*pow(Q,(i-j-1)*(i-j)//2,M)*P
    q[i]%=M
print(sum(q[i]*pow(Q,(T-i)*(T-i+1)//2,M) for i in range(T+1))%M)