Challenge to solve: Connect to a PostgreSQL database and retrieve sales data for the past month. Clean the data by handling missing values, outliers, and inconsistencies. Then, transform the data to calculate daily sales totals, product category breakdowns, and identify top$-$selling products.

$10$

The solution should be a step$-$by$-$step, package installation to Data Transformation.

Challenge: You're tasked with analyzing a datuset on global flight delays $($e$.$g$.,$ origin, destination, delay minutes, airline$).$ Create a compelling data visualization story in R to uncover insights about flight delays.

$10$

The solution should be a step$-$by$-$step, from package installation.