Which of the following tasks can a firewall perform?

A firewall is a security device or software that monitors and controls incoming and outgoing network traffic based on predetermined security rules. Its primary purpose is to establish a barrier between a trusted internal network and untrusted external networks, such as the internet. By isolating internal and external network traffic, the firewall helps protect sensitive data and resources from unauthorized access or attacks. This function is crucial for maintaining the security and integrity of an organization's network environment.

The other tasks mentioned do not fall within the capabilities or functions of a firewall. Tracking individual user expenses is more aligned with financial management tools rather than network security. Recommending credit products to consumers involves insight into consumer behavior and needs, which is not a function of a firewall. Similarly, calculating loan interest rates pertains to financial services and calculations, which are unrelated to network security and the functions of a firewall.