#include <bits/stdc++.h>

int ri() {
	int n;
	scanf("%d", &n);
	return n;
}
#define MOD 1000000007

template<int mod>
struct ModInt{
	int x;
	ModInt():x(0){}
	ModInt(long long y):x(y>=0?y%mod:(mod-(-y)%mod)%mod){}
	ModInt &operator+=(const ModInt &p){
		if((x+=p.x)>=mod)x-=mod;
		return *this;
	}
	ModInt &operator-=(const ModInt &p){
		if((x+=mod-p.x)>=mod)x-=mod;
		return *this;
	}
	ModInt &operator*=(const ModInt &p){
		x=(int)(1LL*x*p.x%mod);
		return *this;
	}
	ModInt &operator/=(const ModInt &p){
		*this*=p.inverse();
		return *this;
	}
	ModInt &operator^=(long long p){
		ModInt res = 1;
		for (; p; p >>= 1) {
			if (p & 1) res *= *this;
			*this *= *this;
		}
		return *this = res;
	}
	ModInt operator-()const{return ModInt(-x);}
	ModInt operator+(const ModInt &p)const{return ModInt(*this)+=p;}
	ModInt operator-(const ModInt &p)const{return ModInt(*this)-=p;}
	ModInt operator*(const ModInt &p)const{return ModInt(*this)*=p;}
	ModInt operator/(const ModInt &p)const{return ModInt(*this)/=p;}
	ModInt operator^(long long p)const{return ModInt(*this)^=p;}
	bool operator==(const ModInt &p)const{return x==p.x;}
	bool operator!=(const ModInt &p)const{return x!=p.x;}
	explicit operator int() const { return x; }						   // added by QCFium
	ModInt operator=(const int p) {x = p; return ModInt(*this);} // added by QCFium
	ModInt inverse()const{
		int a=x,b=mod,u=1,v=0,t;
		while(b>0){
			t=a/b;
			a-=t*b;
			std::swap(a,b);
			u-=t*v;
			std::swap(u,v);
		}
		return ModInt(u);
	}
	friend std::ostream &operator<<(std::ostream &os,const ModInt<mod> &p){
		return os<<p.x;
	}
	friend std::istream &operator>>(std::istream &is,ModInt<mod> &a){
		long long x;
		is>>x;
		a=ModInt<mod>(x);
		return (is);
	}
};
typedef ModInt<MOD> mint;

struct MComb {
	std::vector<mint> fact;
	std::vector<mint> inversed;
	MComb(int n) { // O(n+log(mod))
		fact = std::vector<mint>(n+1,1);
		for (int i = 1; i <= n; i++) fact[i] = fact[i-1]*mint(i);
		inversed = std::vector<mint>(n+1);
		inversed[n] = fact[n] ^ (MOD-2);
		for (int i = n - 1; i >= 0; i--) inversed[i]=inversed[i+1]*mint(i+1);
	}
	mint ncr(int n, int r) {
		return (fact[n] * inversed[r] * inversed[n-r]);
	}
	mint npr(int n, int r) {
		return (fact[n] * inversed[n-r]);
	}
	mint nhr(int n, int r) {
		assert(n+r-1 < (int)fact.size());
		return ncr(n+r-1, r);
	}
};

int main() {
	int n = ri();
	std::vector<int> hen[n];
	for (int i = 1; i < n; i++) {
		int a = ri() - 1;
		int b = ri() - 1;
		hen[a].push_back(b);
		hen[b].push_back(a);
	}
	int parent[n];
	parent[0] = -1;
	std::queue<int> que;
	que.push(0);
	while (que.size()) {
		int i = que.front();
		que.pop();
		for (auto j : hen[i]) if (j != parent[i]) parent[j] = i, que.push(j);
	}
	
	int ok[n];
	memset(ok, 0, sizeof(ok));
	int m = ri();
	for (int i = 0; i < m; i++) {
		int x = ri() - 1;
		int y = ri() - 1;
		std::vector<int> r0, r1;
		while (x != -1) r0.push_back(x), x = parent[x];
		while (y != -1) r1.push_back(y), y = parent[y];
		while (r0.size() && r1.size() && r0.back() == r1.back()) r0.pop_back(), r1.pop_back();
		for (auto j : r0) ok[j] |= 1 << i;
		for (auto j : r1) ok[j] |= 1 << i;
	}
	std::vector<std::vector<int64_t> > dp(n + 1, std::vector<int64_t> (1 << m));
	dp[0][0] = 1;
	for (int i = 0; i < n; i++) {
		for (int j = 0; j < 1 << m; j++) {
			// use
			if (i) dp[i + 1][j | ok[i]] += dp[i][j];
			// no use
			dp[i + 1][j] += dp[i][j];
		}
	}
	std::cout << dp[n][(1 << m) - 1] << std::endl;
	
	return 0;
}


Measured memory_bytes: 426496