please explain

Nitric acid (HNO3) is a strong acid that is one contributor to acid rain. The precursor of HNO3 is nitrogen dioxide (NO2), a gas formed during combustion processes. Consider a region with heavy car traffic, where the HNO2 concentration is 6.8 HNO3 in the air. What would you expect the pH to be in a cloud with liquid water content 0.30 g/m (liquid water content here refers to the mass of water per volume air)? Assume that all the HNO3 dissolves into the water. Enter your answer correct to one decimal place