import java.io.*;
import java.util.*;

public class Maarten {
    public static void main(String[] args) throws IOException {
        try (BufferedReader reader = new BufferedReader(new InputStreamReader(System.in))) {
            new Maarten().run(reader);
        }
    }

    public void run(BufferedReader reader) throws IOException {
        String[] firstLine = reader.readLine().split(" ");
        int n = Integer.parseInt(firstLine[0]);
        int q = Integer.parseInt(firstLine[1]);

        Map<String, Map<String, Double>> units = new HashMap<>();
        for (int i = 0; i < n; i++) {
            String[] line = reader.readLine().split(" = ");
            String a = line[0].substring(2);
            String[] split = line[1].split(" ");
            double x = Double.parseDouble(split[0]);
            String b = split[1];
            if (!units.containsKey(a)) units.put(a, new HashMap<>());
            if (!units.containsKey(b)) units.put(b, new HashMap<>());
            units.get(a).put(b, x);
            units.get(b).put(a, 1 / x);
        }

        for (int i = 0; i < q; i++) {
            String[] line = reader.readLine().split(" to ");
            String[] split = line[0].split(" ");
            double x = Double.parseDouble(split[0]);
            String a = split[1];
            String b = line[1];

            HashMap<String, Double> seen = new HashMap<>();
            seen.put(a, x);
            Queue<String> todo = new LinkedList<>();
            todo.add(a);
            while (!todo.isEmpty()) {
                String curr = todo.peek();
                if (curr.equals(b)) {
                    System.out.println(seen.get(b));
                    break;
                }
                todo.remove();
                units.get(curr).forEach((k, v) -> {
                    if (!seen.containsKey(k)) {
                        seen.put(k, seen.get(curr) * v);
                        todo.add(k);
                    }
                });
            }
            if (todo.isEmpty()) System.out.println("impossible");
        }
    }
}