The balance of oxygen in earth's atmosphere is maintained primarily by which two processes?

a.
photosynthesis and respiration

b.
outgassing and photosynthesis

c.
lightning and fixation by bacteria

d.
the formation of carbonate rocks and outgassing

Let hh represent the number of hummingbirds and ss represent the number of sunbirds that must pollinate the colony so it can survive until next year. 6h+4s > 746h+4s> 74 this year, 88 hummingbirds pollinated the colony. what is the least number of sunbirds that must pollinate the colony to ensure that it will survive until next year?