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#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<int,int>pii;
const int maxn=2e5+10,inf=0x3f3f3f3f,mod=1000000007;
ll gcd(ll a,ll b)
{
if(a<b)
swap(a,b);
ll r;
while((r=a%b)){
a=b;
b=r;
}
return b;
}
ll lcm(ll a,ll b)
{
return (a*b)/gcd(a,b);
}
map<int,int>mp;
struct MCMF
{
struct Edge
{
int from, to, cap, flow, cost;
Edge(int u, int v, int c, int f, int w)
: from(u), to(v), cap(c), flow(f), cost(w) {}
};
int n, m;
vector<Edge> edges;
vector<int> G[maxn];
int inq[maxn];
int d[maxn];
int p[maxn];
int a[maxn];
void init(int n)
{
this->n = n;
for (int i = 0; i <= n; i++)
G[i].clear();
edges.clear();
}
void AddEdge(int from, int to, int cap, int cost)
{
edges.push_back(Edge(from, to, cap, 0, cost));
edges.push_back(Edge(to, from, 0, 0, -cost));
m = edges.size();
G[from].push_back(m - 2);
G[to].push_back(m - 1);
}
bool BellmanFord(int s, int t, int& flow, ll& cost)
{
for (int i = 0; i < n; i++)
d[i] = inf;
memset(inq, 0, sizeof(inq));
d[s] = 0;
inq[s] = 1;
p[s] = 0;
a[s] = inf;
queue<int> q;
q.push(s);
while (!q.empty())
{
int u = q.front();
q.pop();
inq[u] = 0;
for (int i = 0; i < G[u].size(); i++)
{
Edge& e = edges[G[u][i]];
if (e.cap > e.flow && d[e.to] > d[u] + e.cost)
{
d[e.to] = d[u] + e.cost;
p[e.to] = G[u][i];
a[e.to] = min(a[u], e.cap - e.flow);
if (!inq[e.to])
{
q.push(e.to);
inq[e.to] = 1;
}
}
}
}
if (d[t] == inf)
return false;
flow += a[t];
cost += (ll)d[t] * (ll)a[t];
mp[d[t]*a[t]]+=a[t];
for (int u = t; u != s; u = edges[p[u]].from)
{
edges[p[u]].flow += a[t];
edges[p[u] ^ 1].flow -= a[t];
}
return true;
}
int MincostMaxflow(int s, int t, ll& cost)
{
int flow = 0;
cost = 0;
while(BellmanFord(s, t, flow, cost));
return flow;
}
} mm;
int cost[maxn];
signed main()
{
#ifdef DEBUG
freopen("input.in", "r", stdin);
#endif
ll n,m,u,v,w,c,q;
while(~scanf("%lld%lld",&n,&m))
{
mm.init(n+10);
mp.clear();
for(int i=1;i<=m;i++)
{
scanf("%lld%lld%lld",&u,&v,&cost[i]);
mm.AddEdge(u,v,1,cost[i]);
}
ll tot=0,mf=mm.MincostMaxflow(1,n,tot);
scanf("%lld",&q);
while(q--)
{
scanf("%lld%lld",&u,&v);
if(mf*u<v)
puts("NaN");
else{
ll now=0,x=0,y=v;
for(auto &i:mp)
{
if(v>i.second*u)
{
v-=i.second*u;
x+=i.first*u;
}
else{
x+=i.first*v/i.second;
break;
}
}
ll g=gcd(x,y);
printf("%lld/%lld\n",x/g,y/g);
}
}
}
return 0;
}
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