In my opinion Becker does a poor job explaining trusts and estates. Why would you include Adjusted tax-exempt interest in the distributable net income (DNI) formula when you're just going to subtract it out again when determining the income distribution deduction which is the lesser of Actual distribution or DNI)
I also think that it isn't such a greatly tested area, but would suggest you to go through NINJA Sparring if you have access, and listen to that lecture it goes through all trusts topics. But I heard that a lot of trust has been omitted as per July 2021 Blue print check it out and ask around. I also tested REG last week and waiting for my score, Just like @Brittany.MCGuire.