Response: OpenSCAD is a great, powerful tool for making 3D models for anyone with some programming/scripting experience.
Response: Mainly selling on ebay currently. However, I've made most income over my career from working as Web Developer for a single employer. I also trade stocks on TD Ameritrade.
Response: Inkjet ink is one of the most expensive liquids by weight. Some inkjet printers can be configured to have nearly unlimited ink using a continuous ink supply system (CISS). Search keywords, "epson ciss". Epson has models that use 4 colors of dye sublimation ink: cyan, magenta, yellow, and black. Search keywords: "epson ink refill". Ink refills cost around $30 for a full set. Those are cheaper than using 6 colors printers.
These Epson printers can be flushed with special cleaning fluid. Search keywords "Printhead Cleaning Kit Printer Flush Kit".
The printer I use is an Epson Workforce 2760. If you search on Ebay or Amazon, you will find similar printers.
Epson has their own version CISS called eco tank. They are more expensive than a CISS kit.
One downside of some CISS is that if there is a power outage, the system must be reset using a button to simulate changing the cartridges.
Response: Yes, set up the port so that it forwards to your computer LAN IP address. Run the program "netcat" with arguments "-l [PC port]" so it listens on that port. (Netcat can be downloaded on Windows using Cygwin). Then run another instance of netcat and connect to the Internet IP address: "nc [your WAN IP] [your WAN port]". If port forwarding is working, you can type text into the client and see it on server.
Response: Download and run Streamripper:
streamripper.exe [stream URL] --xs2 -d [save folder] -m 1200 -o always
Response: Yes, you can install rear axle tensioners on the rear bolts.
Cheap type: https://www.aliexpress.com/item/2251832780835077.html
Better type: https://www.amazon.com/Origin8-Chain-Tension-Adjuster-Black/dp/B001GPJY1O/
Take off the rear nuts, install the tensioners between the threads and the nuts. Tighten the tensioner so that the chain has reasonable tension. Then screw the rear axle nuts back on. The tensions hold the wheel against the frame so it can't slide forward.
Response: Person with intermediate-level experience and knowledge on the topics above.
Response: You can just append the binary files together then use a program such as mp3val (free program) to fix the mistakes. You won't be able to hear the difference. This method is much faster than joining mp3 files in a standard way.
Response: I use Google Drive for Google Docs. My little home server hosts a lot of different types of files: video DVR for ATSC, FiOS, security cameras, etc.
Response: It takes about 1-2 weeks to study the questions. There are three difficulty levels that determine your rank as an amateur radio operator. The passing score is forgiving so you can get some wrong. It's $15. It allows you to transmit over the radio pretty far away depending on your equipment and antenna. You don't need a license to receive radio signals. You can receive using a device such as the HackRF software-defined radio.