Trial Duration In JavaScript

[carrie13]

I'm attempting to write an experiment that will require 4 basic parts: a fixation cross, an instruction, an experimental stimulus, and a rating scale. I switched the language to JavaScript from JSPsych per the request of my instructor, but I'm now having trouble translating certain plugins from the JSPsych library to basic JavaScript code.
Each of the parts listed above will need a trial duration. For example the fixation cross needs to be shown for 2 seconds, the instructions for 4 seconds, and so on. I'm pretty sure I can loop through the trials, I just need help with how to set up a variable to show the pictures for a specific amount of time.
Thanks!