ICD-9 coding for pneumonia

1.A patient is diagnosed with streptococcal pneumoniae pneumonia with hypoxemia. What is the correct code(s)?

2.A patient is admitted to the hospital with respiratory failure due to pneumonia. During the course of the admission, both conditions were equally treated and documented as definitive discharge diagnoses. What is the correct code sequence for this inpatient admission?

3.An inpatient is diagnosed on discharge with a principal diagnosis of pneumonia. During the admission, a sputum culture is performed revealing it is positive for gram-negative bacteria. What is the correct code(s) based on this documentation?

4.The most common form of pneumonia associated with HIV/AIDS is:

5.A common medication used to treat bacterial pneumonia is: