#include <bits/stdc++.h>
using namespace std;
typedef long long int ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef long double ld;
#define F first
#define S second
#define pb push_back
#define endl '\n'
#define Mp make_pair
#define all(x) x.begin(), x.end()
#define debug(x) cerr << #x << " = " << x << endl;
#define fast_io ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
#define file_io freopen("input19.txt" , "r" , stdin) ;
const int N = 3e5+23;
ll c[N], ans[N], seg[4*N], lpz[4*N];
vector<pii> in[N];
ll d;
int n, q;
vector<pair<pll, pll> > st; // Mnc, Mxc, l, r
void Shift(int l, int r, int ind){
if(r-l==1) return;
if(!lpz[ind]) return;
int mid=(r+l)>>1;
seg[2*ind+1]+=(mid-l)*lpz[ind];
lpz[2*ind+1]+=lpz[ind];
seg[2*ind+2]+=(r-mid)*lpz[ind];
lpz[2*ind+2]+=lpz[ind];
lpz[ind]=0;
}
void upd(int lx, int rx, ll x, int l=1, int r=n+1, int ind=0){
Shift(l, r, ind);
if(lx>=r || rx<=l) return;
if(lx<=l && rx>=r){
seg[ind]+=x*(r-l);
lpz[ind]+=x;
return;
}
int mid=(r+l)>>1;
upd(lx, rx, x, l, mid, 2*ind+1); upd(lx, rx, x, mid, r, 2*ind+2);
seg[ind]=seg[2*ind+1]+seg[2*ind+2];
}
ll get(int lx, int rx, int l=1, int r=n+1, int ind=0){
Shift(l, r, ind);
if(lx>=r || rx<=l) return 0;
if(lx<=l && rx>=r) return seg[ind];
int mid=(r+l)>>1;
return get(lx, rx, l, mid, 2*ind+1)+get(lx, rx, mid, r, 2*ind+2);
}
int main()
{
cin>>n>>d;
for (int i=1; i<=n; i++) cin>>c[i];
cin>>q;
for(int i=0; i<q; i++){
int l, r; cin>>l>>r;
in[r].pb({l, i});
}
for (int i=1; i<=n; i++){
while(!st.empty() && st.back().F.S>c[i]){
ll Mnc=st.back().F.F, Mxc=st.back().F.S, l=st.back().S.F, r=st.back().S.S;
st.pop_back();
ll x=(Mxc-c[i]+d-1)/d;
if(!st.empty()) x=min(x, (Mnc-st.back().F.S)/d);
upd(l, r+1, x);
Mnc-=x*d; Mxc-=x*d;
if(!st.empty() && Mnc-st.back().F.S<d) {
Mnc=st.back().F.F;
l=st.back().S.F;
st.pop_back();
}
st.pb({{Mnc, Mxc}, {l, r}});
}
st.pb({{c[i], c[i]}, {i, i}});
for (auto pp: in[i]){
if(c[pp.F]-get(pp.F, pp.F+1)*d<0) ans[pp.S]=-1;
else ans[pp.S]=get(pp.F, i+1);
}
}
for (int i=0; i<q; i++) cout<<ans[i]<<endl;
}
