❔ How do I use LINQ to get Friends younger than 50?

    class Friend
    {
        public DateTime BirthDate;
        public string PhoneNumber;
        public string Name;
        public string Id;
        public Friend(string name, string BirthDate, string PhoneNumber)
        {
            this.Name = name;
            this.BirthDate = DateTime.Parse(BirthDate);
            this.PhoneNumber = PhoneNumber;
            this.Id = Guid.NewGuid().ToString();
        }
        public Friend(string name, DateTime BirthDate, string PhoneNumber)
        {
            this.Name = name;
            this.BirthDate = BirthDate;
            this.PhoneNumber = PhoneNumber;
            this.Id = Guid.NewGuid().ToString();
        }
    }

var friends = new List<Friend>{
                new Friend("Linus", "01/01/1970", "707-419-4447"),
                new Friend("Scott", "10/10/1970", "801-224-7513"),
                new Friend("Charlie", DateTime.Parse("01/01/1999"), "801-225-8597")
            };

var youngFriendsQuery =
            from friend in friends
            where (friend.BirthDate - now).TotalDays < 50*365
            select friend;