Cross-platform measurement: The number of marketing channels continues to expand, as measurement practices are growing in complexity. A cross-platform view must be used to unify audience measurement and media planning. Market researchers need to understand how the Omni-channel affects consumer's behaviour, although when advertisements are on a consumer's device this does not get measured. Significant aspects to cross-platform measurement involves de-duplication and understanding that you have reached an incremental level with another platform, rather than delivering more impressions against people that have previously been reached (Whiteside, 2016).[42] An example is ‘ESPN and comScore partnered on Project Blueprint discovering the sports broadcaster achieved a 21% increase in unduplicated daily reach thanks to digital advertising’ (Whiteside, 2016).[42] Television and radio industries are the electronic media, which competes with digital and other technological advertising. Yet television advertising is not directly competing with online digital advertising due to being able to cross platform with digital technology. Radio also gains power through cross platforms, in online streaming content. Television and radio continue to persuade and affect the audience, across multiple platforms (Fill, Hughes, & De Franceso, 2013).[45]
The topic you choose must have enough depth that you can create a lot of content for it. This is important for building an authoritative site, for search engine optimization, and most importantly, for the end user. If you don't have enough content about a topic, you're not going to be taken very seriously as an authority on the topic and it's unlikely you can convince someone to make a purchase from you. 

Daily Surveys can be taken one or more times per day. This is indicated in the survey description. Other targeted surveys can be taken as you see them. Be sure to complete these when you see them. Some surveys may accept a limited number of responses from people matching your demographics, and can sometimes disappear quickly. New surveys come out all the time too!
Yes and no. Affiliate marketing can generate passive income, but the passive side of the income usually only follows putting in a few years of hard work to generate the brand and audience you'll need to begin generating those passive sales. I have multiple sites earning passive income, but each of those sites took a lot of front end work to build up to that point. And not every site gets to the point of passive income. Some sites require continual maintenance though the revenue they generate can also allow you to pay for that maintenance to be done vs. you needing to do it yourself.
If you are a creative type, then you could make money online by designing and selling crafty products on Etsy. Etsy sells a range of beautiful and original items from independent suppliers. Categories range from jewelry, clothes, and accessories, to art, collectibles, and vintage. So if you have some stunning crafty creations, Etsy is the perfect platform from which to sell from.

If you’re looking for inspiration, my friend Michelle Schroeder-Gardner of the website Making Sense of Sense has become the expert on all things affiliate marketing. Michelle earns more than $100,000 per month from her blog and the bulk of her income comes from affiliate sales. Michelle has had so much success with affiliate marketing that she even has her own course called Making Sense of Affiliate Marketing.