Time lines are used to help visualize what is happening in time value of money problems. Cash flows are placed directly below the tick marks, and interest rates are shown directly above the time line; unknown cash flows are indicated by a symbol for the particular item that is missing.
This page explains how you can apply a patch file. Patch is a standard format, and there are many options for how to apply one. Pick the one that is easiest for you. Perhaps most critical is the usage of the -p flag, which tells patch about the relationship between the directory where the patch file is located and the files that will be patched.
A crontab file is a simple text file containing a list of commands meant to be run at specified times. It is edited using the crontab command. The commands in the crontab file (and their run times) are checked by the cron daemon, which executes them in the system background. Each user (including root) has a crontab file.