No, this only works in a range of up to 16 feet from your camera. I'm not sure what you would do for your situation; it sounds like a computer solution might be appropriate.
No, the ML-L3 Wireless Remote is not compatible with the Coolpix A900. If you would like to use a wireless remote, you can connect this camera to a phone or smart device by using the Nikon SnapBridge App. This app will have a remote photography function to use your phone or smart device as a remote trigger.
No. Nikon does not make a compatible release remote for the Nikon D3500 DSLR camera. For a remote release option for this camera model, just connect to a smart device that is running the SnapBridge Application. SnapBridge allows you to easily transfer your images as soon as you take them to your favorite smart device and also lets you to take images remotely so you can be in the shot. For more information about SnapBridge, please contact Nikon Support.
No. The Nikon D3500 DSLR camera is not compatible with the ML-L3 Wireless Remote. There are no remote accessories that are compatible with this camera model. For a remote release option for this camera check out Nikon's SnapBridge application. For more information, please contact Nikon Support.
No, the D70 does not have Wi-fi or Bluetooth capabilities and Nikon does not make a Wi-fi adapter that is compatible with the D70. However, the D70 is compatible with this ML-L3 Wireless Remote Control (Product 4730) since the ML-L3 uses infrared signals to trigger the camera. Information on using the ML-lL3 with the D70 can be found in the D70 manual.