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The Security Issue fix may go out as a Hot Fix but will definitely be out by the next release.

Scenario (Follow-Up):You previously discovered, through a FULL JOIN between Sales and Customers, that Gulf Coast Retail’s June 2025 data contain: Sales transactions with null Customer fields, and Customer records with null Sales fields.You also have access to Employee ID and Payment Method information for each transaction.   Question: Explain how these data integrity issues could affect financial reporting, audit testing, and management decision-making at Gulf Coast Retail.Describe the controls or reconciliation steps you would recommend before the monthly financial close.      

While preparing data for Gulf Coast Retail’s sales analysis, you performed a FULL JOIN between the Sales table and the Customers table.The results revealed: Several records where Sales data exist but Customer fields are null. Several records where Customer data exist but Sales fields are null. Additional fields in the dataset include Employee ID (sales representative) and Payment Method (cash, credit, financing, etc.).   Question:Explain the potential business implications of each type of null value, and describe how you would investigate or address these issues using the additional information provided.      

SUBJUNTIVO: WILL and INFLUENCE.  Mira la imágenes y usa los verbos en paréntesis para completar las oraciones en el subjuntivo.   Imagen #1 Joaquín, es importante que nosotros (ir) [1] y que (comprar) [2] los materiales de arte en la tienda.   Imagen #2 Teresa, es mejor que tú no (mirar) [3] y que (correr) [4] rápidamente.   Imagen #3 Georgina dice: ¡Qué interesante que ustedes (cantar) [5] y que también (tocar) [6] la guitarra!   Imagen #4 El hombre muy malo dice: “Señor, es mejor que usted (levantar) [7] las manos y que me (dar) [8] su dinero!   Imagen #5 Susana, es importante que nuestra (our) hermana (llegar) [9] pronto y que (ser) [10] puntual.  

Finally, assume you want to compare the k-NN model above against a regression tree model which you train on the same data. You obtain the following error metrics for the regression tree:   Regression Tree Mean Error: 1200 RMSE: 5430   Compare the ME and RMSE obtained above for the k-NN model to the ME and RMSE of the tree. You need to decide which model you would recommend your company to use. In making your choice, assume that the listing price of a house cannot be increased after it is set. If the listing price is too high, buyers can try to negotiate a lower price. But if the listing price turns out to be low, the seller cannot increase it.  

Assume you test the decision tree created above on a sample of 100 observations and obtain the following confusion matrix. In the testing data, you have 80 NO SPAM and 20 YES SPAM.       ACTUAL CLASS     YES SPAM NO SPAM PREDICTED CLASS YES SPAM 5 (TP) 5 (FP) NO SPAM 15 (FN) 75 (TN)

Which of the following statements about the Entropy of the partition/node “Do you know the sender?” = NO (the green node with YES SPAM, 0.61 and 6%) is TRUE?

Which of the following statements about Decision Trees is FALSE? 

Which of the following statements is FALSE about the difference between unsupervised and supervised learning?

Which of the following statements about lift in Association Rules is FALSE?