Lightroom 5.0 Export Settings- Resolution?

[Louie9190]

I am new to this. From reading online and talking to friends, there should be a way to set the resolution of my photos when I export them. I can't find this setting anywhere. I have attached a screengrab of my export settings menu. There's nothing about resolution. I use a PC if that helps. Please help?

[Rikk Flohr: Photography]

Set Pixels to Inches and it will appear

[Louie9190]

Thank you! This was so helpful! Next question- All of the information for exporting that I can find online is for Lightroom Classic, where most users are not resizing the image, just simply setting resolution to 300. On my Lightroom CC, it appears that I am REQUIRED to set the "long side- inches" in order to adjust the resolution to 300 as you mentioned above. So, my question is, do I have to export a new file for each size photo I want to print? Or can I set the long side inches to a certain number that will work and look good for any size print? (with resolution staying at 300).

[Rikk Flohr: Photography]

The best bet is to check the pixel dimensions of the file in the info panel and use that value at 300 if having that header flag set to 300 is critical.
Most people just export at full size and ignore the 300 as the file doesn't change substanitively - just the DPI value in the header.