Amazon hopped on the voice assistant train a few years ago with the Echo, and has since added its Alexa platform to a myriad of products. While Alexa is great at things like controlling smart home devices, its ability to answer multiple queries is not so great. It appears to be getting better, though. Amazon has added some limited contextual awareness to Alexa.
Based on what others are saying around the web and our own testing, you can now ask Alexa basic questions about something you've already established. For example, ask it who the president is, then in a second query ask how old he is. Alexa can do this now. It can even carry on longer conversations about a single topic, but not all topics. It seems to be able to remember when you're talking about a person pretty well. Some questions just don't work, and it sounds like this functionality may be US-only right now.
This is a nice improvement for Alexa, but Google Home is still vastly better at this sort of thing. Not only does it understand context better, it has a lot more data to draw from thanks to Google's Knowledge Graph. Amazon is clearly still working on context, so I'm sure it'll get better. Still a long way to go before it catches up to Google, if it ever does.