diff --git a/app.py b/app.py
index e293225..d029c20 100644
--- a/app.py
+++ b/app.py
@@ -1 +1,51 @@
-# Your DB Code Here
+URL = DB_LINK.format(
+    DB_USERNAME, DB_PWD)
+
+client = pymongo.MongoClient(URL)
+db = client["RHDEVS-BE-Mongo"]
+
+
+#1
+pipeline1 = [{"$group": 
+            {"_id": "$isbn", 
+            "number_of_entries" : {"$sum":1}}}]
+print(list(db.sellingdata.aggregate(pipeline1)))
+
+#2
+pipeline2 = [{"$group" : {"_id": "$isbn","number_of_copies": {"$sum": "$copies_sold"}}},
+              {"$project" : {"_id" : 1,"number_of_copies" : 1}},
+              {"$match" : {"number_of_copies" : {"$gte" : 15000}}},
+              {"$lookup" : {"from": 'books', "localField": '_id', "foreignField": 'isbn',"as": 'details'}},
+              {"$project" : {"number_of_copies" : 0, "_id" :0}},
+              {"$set" : {"titledetails" : "$details.title"}},
+              {"$project" : {"details":0}}
+              ]
+
+print(list(db.sellingdata.aggregate(pipeline2)))
+
+#3
+print(list(db.books.find({"author":"John Doe"})))
+
+pipeline3 = [{"$group": {"_id": "$author","isbn" : {"$addToSet" : "$isbn"},"titles": {"$addToSet": "$title"},  "number_of_books": {"$sum":1}}},
+              {"$sort": {"isbn":1}},
+              {"$project" : {"isbn" : 0}},
+              {"$match" : {"_id":"John Doe"}},
+              ]
+
+print(list(db.books.aggregate(pipeline3)))
+
+#4
+pipeline4 = [{"$addFields":{"price_per_book": {"$divide": ["$total_price","$copies_sold"]}}},
+              {"$project":{"_id":0, "order_id":1, "price_per_book":{"$round" : ["$price_per_book",2]}}}]
+
+print(list(db.sellingdata.aggregate(pipeline4)))
+
+#5
+
+pipeline5 = [{"$unwind" : {"path": "$supplier"}},
+              {"$match" : {"supplier" : "titan"}},
+              {"$group" : {"_id": "$supplier", "total_copies" : {"$sum" : "$copies_sold"},  "sum_price" : {"$sum": "$total_price"}}},
+              {"$addFields": {"average_per_book" : {"$divide" : ["$sum_price","$total_copies"]}}},
+              {"$project": {"_id":1, "average_per_book" : {"$round" : ["$average_per_book",2]}}}]
+
+print(list(db.sellingdata.aggregate(pipeline5)))