Sure! I'd be happy to help!
For part A:
b < 28
There's nothing to solve as this is a simple inequality where the solution is all real numbers less than 28. The solution is: b is any real number less than 28.
For part D:
n < 56
Same as part A, there's nothing to solve as this is a simple inequality where the solution is all real numbers less than 56. The solution is: n is any real number less than 56.
If you need further clarification, feel free to ask!