Can you wear these socks if the temp is 80 or above?

Yes, but you may want to consider a sock with a higher percentage of synthetic. This will move the moisture away from your foot better, especially if you have sweaty feet. Try the Teko Synrgi series. http://www.backcountry.com/teko-midweight-hiking-sock-mens.html

They'll be pretty hot for that, I'd recommend the "Light" weight ones for hot-weather hiking or running. I use these for trail running and hiking: http://www.backcountry.com/smartwool-phd-running-ultra-light-mini-sock