import java.util.Scanner;

public class PicuBank {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int t = sc.nextInt();
		while (t-- > 0) {
			int d = sc.nextInt();
			int a = sc.nextInt();
			int m = sc.nextInt();
			int b = sc.nextInt();
			int x = sc.nextInt();
			System.out.println(check(d, a, m, b, x));
		}
	}

	private static int check(int d, int a, int m, int b, int x) {
		int months = 0;
		int direct = (a*m)+b;
		int dir_months = m+1;
		int dhan_rashi = d;
		while (dhan_rashi < x) {
			if (months != 0 && months % m == m - 1) {
				dhan_rashi += b;
				dhan_rashi += a;
				months += 2;
				// System.out.println(dhan_rashi + "-->" + months);
			}
			if (months % m != m - 1 || months == 0) {
				dhan_rashi += a;
				months++;
				// System.out.println(dhan_rashi+ "-->" + months);
			}
		}
		return months;
	}

}