Update standard-questions.md

[ricardomiron]

Fix typos

Propagation of Changes

Identify where of the following the proposed changes need to be propagated, and include the relevant pull request where appropriate:

• The DPGA website contains https://digitalpublicgoods.net/standard/ which needs to be updated manually matching the contents of standard.md.
• The DPGA website also contains the submission guide which needs to be updated manually.
• The DPG application webapp admin panel which will be updated manually.
• The Eligibility Form through the unicef/publicgoods-scripts repository, by editing quizQuestions.js