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In response to question 1, yes but you should also include your root as the "X-Default" hreflang (https://support.google.com/webmasters/answer/189077?hl=en). In respoonse to question 2, yes but the problem with this approach is that you will not be able to target the root domain, otherwise it will impact all your subdirectories too. So, you'll have to leave the root domain untargeted. There are pros/cons, but this is one of the cons of using subdirectories instead of subdomains.