#include <bits/stdc++.h>
#define fst first
#define snd second
#define pb push_back
#define SZ(x) (int)x.size()
#define ALL(x) x.begin(),x.end()
#define forn(i,a,b) for(int i = a; i<b; i++)
#define mset(a,v) memset(a,v,sizeof(a))
#define FIN ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
using namespace std;
typedef long long ll;
const int MAXN = 200000+5;
#define INF 99999999999999999;
ll n,q;
ll red[MAXN];
ll blue[MAXN];
vector<ll> adj[MAXN];
ll dp[MAXN][10];
ll cen;
// diferencia red-blue
/*
0=-2
1=-1
2=0
3=1
4=2
*/
vector<ll> dif = {-2,-1,0,1,2};
void expand(ll nd, ll p){
//cout<<"expand to "<<nd<<'\n';
if(p==-1){
dp[nd][3]=max(dp[nd][3] , red[nd]);
dp[nd][1]=max(dp[nd][1] , blue[nd]);
}else{
forn(t, 0, 5){
if(t-1>=0) dp[nd][t]=max( dp[nd][t] , dp[p][t-1]+red[nd] );
if(t+1<5) dp[nd][t]=max( dp[nd][t] , dp[p][t+1]+blue[nd] );
//cout<<"dp "<<t<<" "<<dp[nd][t]<<'\n';
}
}
for(auto i:adj[nd]) if(i!=p){
expand(i,nd);
}
}
int main(){
cin>>n>>q;
forn(i,0,n) cin>>red[i];
forn(i,0,n) cin>>blue[i];
ll u,v;
forn(i,0,n-1){
cin>>u>>v; u--; v--;
adj[u].pb(v);
adj[v].pb(u);
}
forn(i,0,q){
cin>>u>>v; u--; v--;
forn(j,0,MAXN) forn(k,0,10) dp[j][k]=-INF;
expand(u,-1);
ll res = -INF;
forn(t,0,5) res=max(res,dp[v][t]);
cout<<res<<'\n';
}
return 0;
}
