Learning Linux - How to tell if PHP is running on RedHat 7.2

Hoping someone could help. I'm new to Linux and have been asked how to tell if PHP is running on their server. I assume there are dozens or hundreds of specific modules. I see that the rpm's for PHP were installled, but I'm not sure if it has been compiled to work with MySQL and Apache nor if PHP is even active on the server. Is there a specific command to type besides ps -aux that will allow me to see if PHP is active?

Thanks,

jbm