To present a slide show I downloaded the Chrome browser. to show the browser screen on the Chromecast receiver monitor/TV. For the slideshow I added the Chrome browser iSlide extension. I found that I could not use it directly to present a folder of photos on the laptop.
Gas-fired water heaters require a mechanical permit and electrical water heaters need a plumbing permit to ensure that the unit is installed properly with a temperature and pressure relief valve, the valve has an attached drainpipe, and the entire system is installed in a safe location.
When shopping for your water heater, you'll want to check your state's requirements. Sears carries a number of gas water heaters that are compliant with California state laws. Even if you don't live in a state with specific requirements, you fan find a wide variety of options that will best suit your water usage needs.