Which three are true about converting a tabular, summary, or matrix report to a joined report? (Choose three.)

Which two are features of Schema Builder? (Choose two.)

An app builder wants to prevent users from creating new records on an account related list by overriding standard buttons.
Which two aspects should be considered before overriding standard buttons? (Choose two.)

An app builder wants to show Groups as the last navigation menu item in the Salesforce Mobile App.
However, the app builder is not able to select Groups as one of the items on the drop-down menu.
What could cause this?

An app builder creates an Account validation rule on the Industry field that will throw an error if the length of the field is longer than 6 characters. Another app builder creates a workflow with a field update that sets the Industry field to Technology whenever the Billing City field is set to San Francisco.
What will happen the next time a sales person saves an Account with a Billing City of San Francisco?