#include<cstdio>

#include<algorithm>

#include<queue>

using namespace std;

typedef long long ll;

typedef pair<ll,int> P;

const int N=200010;

const ll inf=1LL<<60;

int n,m,que,S,T,i,x,y,g[N],v[N<<1],w[N<<1],nxt[N<<1],ed;

int G[N],V[N],NXT[N],pre[N],d[N];

int path[N],cnt,id[N],fs[N],ft[N];

int q[N],h,t;

ll ds[N],dt[N];

struct E{int x,y,z;}e[N];

priority_queue<P,vector<P>,greater<P> >Q;

inline void read(int&a){char c;while(!(((c=getchar())>='0')&&(c<='9')));a=c-'0';while(((c=getchar())>='0')&&(c<='9'))(a*=10)+=c-'0';}

inline void add(int x,int y,int z){v[++ed]=y;w[ed]=z;nxt[ed]=g[x];g[x]=ed;}

inline void ADD(int x,int y){pre[y]=x;d[y]++;V[++ed]=y;NXT[ed]=G[x];G[x]=ed;}

inline int onpath(int x,int y){

  if(!id[x]||!id[y])return 0;

  if(id[x]+1==id[y])return id[x];

  if(id[y]+1==id[x])return id[y];

  return 0;

}

ll val[525000],ans[N];

void build(int x,int a,int b){

  val[x]=inf;

  if(a==b)return;

  int mid=(a+b)>>1;

  build(x<<1,a,mid),build(x<<1|1,mid+1,b);

}

void change(int x,int a,int b,int c,int d,ll p){

  if(c<=a&&b<=d){val[x]=min(val[x],p);return;}

  int mid=(a+b)>>1;

  if(c<=mid)change(x<<1,a,mid,c,d,p);

  if(d>mid)change(x<<1|1,mid+1,b,c,d,p);

}

void dfs(int x,int a,int b){

  if(a==b){ans[a]=val[x];return;}

  int mid=(a+b)>>1;

  val[x<<1]=min(val[x<<1],val[x]),dfs(x<<1,a,mid);

  val[x<<1|1]=min(val[x<<1|1],val[x]),dfs(x<<1|1,mid+1,b);

}

int main(){

  read(n),read(m);

  for(i=1;i<=m;i++){

    read(e[i].x),read(e[i].y),read(e[i].z);

    add(e[i].x,e[i].y,e[i].z);

    add(e[i].y,e[i].x,e[i].z);

  }

  read(S),read(T);

  if(S==T){

    for(read(que);que--;puts("0"));

    return 0;

  }

  for(i=1;i<=n;i++)ds[i]=inf;Q.push(P(ds[S]=0,S));

  while(!Q.empty()){

    P t=Q.top();Q.pop();

    if(ds[t.second]<t.first)continue;

    for(i=g[x=t.second];i;i=nxt[i])if(ds[x]+w[i]<ds[v[i]])Q.push(P(ds[v[i]]=ds[x]+w[i],v[i]));

  }

  if(ds[T]==inf){

    for(read(que);que--;puts("Infinity"));

    return 0;

  }

  for(ed=0,i=1;i<=m;i++){

    if(ds[e[i].x]+e[i].z==ds[e[i].y])ADD(e[i].x,e[i].y);

    if(ds[e[i].y]+e[i].z==ds[e[i].x])ADD(e[i].y,e[i].x);

  }

  for(i=T;i!=S;i=pre[i])path[++cnt]=i;path[++cnt]=S;

  for(i=1;i<cnt-i+1;i++)swap(path[i],path[cnt-i+1]);

  for(i=1;i<=cnt;i++)id[path[i]]=i;

  for(i=1;i<=n;i++)fs[i]=N;

  for(i=1;i<=cnt;i++)fs[path[i]]=i;

  q[h=t=1]=S;

  while(h<=t)for(i=G[x=q[h++]];i;i=NXT[i]){

    if(!id[V[i]])fs[V[i]]=min(fs[V[i]],fs[x]);

    if(!(--d[V[i]]))q[++t]=V[i];

  }

  for(i=1;i<=n;i++)dt[i]=inf;Q.push(P(dt[T]=0,T));

  while(!Q.empty()){

    P t=Q.top();Q.pop();

    if(dt[t.second]<t.first)continue;

    for(i=g[x=t.second];i;i=nxt[i])if(dt[x]+w[i]<dt[v[i]])Q.push(P(dt[v[i]]=dt[x]+w[i],v[i]));

  }

  for(ed=0,i=1;i<=n;i++)G[i]=d[i]=0;

  for(i=1;i<=m;i++){

    if(dt[e[i].x]+e[i].z==dt[e[i].y])ADD(e[i].x,e[i].y);

    if(dt[e[i].y]+e[i].z==dt[e[i].x])ADD(e[i].y,e[i].x);

  }

  for(i=1;i<=cnt;i++)ft[path[i]]=i;

  q[h=t=1]=T;

  while(h<=t)for(i=G[x=q[h++]];i;i=NXT[i]){

    if(!id[V[i]])ft[V[i]]=max(ft[V[i]],ft[x]);

    if(!(--d[V[i]]))q[++t]=V[i];

  }

  build(1,1,cnt-1);

  for(i=1;i<=m;i++){

    x=e[i].x,y=e[i].y;

    if(onpath(x,y))continue;

    if(fs[x]<N&&ft[y]&&fs[x]<ft[y])change(1,1,cnt-1,fs[x],ft[y]-1,ds[x]+dt[y]+e[i].z);

    if(fs[y]<N&&ft[x]&&fs[y]<ft[x])change(1,1,cnt-1,fs[y],ft[x]-1,ds[y]+dt[x]+e[i].z);

  }

  dfs(1,1,cnt-1);

  read(que);

  while(que--){

    read(x),read(y),i=onpath(x,y);

    if(!i){printf("%lld\n",ds[T]);continue;}

    if(ans[i]<inf)printf("%lld\n",ans[i]);else puts("Infinity");

  }

  return 0;

}