Which natural methods remove co2  from the atmosphere? respiration of living organismsphotosynthesis by plantsevaporation of ocean waterabsorption of co2 from the atmosphere by ocean watermelting of glacial ice

If anyone would be able to me out with these three questions it would be these are from the chem 2202 course.

Ahypothesis must be testable and falsifiable to be considered scientific a. trueb. false

Consider hydrogen in an excited state n = 5n=5 that emits photons to reach the ground state. there are various possible transitions other than straight to the ground state that can occur; for example, it can drop to the n = 3n=3 state followed by the n = 3n=3 to the ground state transition. which of the possible transitions will result in the emission of a photon in the visible region?