<span>If
ever your small boat capsizes in the swift water, all you need to do is to float
on the upstream side of the craft and never try to walk in swift water nor
stand, and this will assure your safety. Also make your feet arms widely opened
or extended with your feet pointed to the downstream.</span>
If CO2 was in very small amounts then it would be the limiting factor of photosynthesis, this means the process will take place at a much slower rate because it is lacking one of the raw materials it needs for the process to occur. To find the optimum light intensity you really need all other factors to be at optimum levels or in abundance.
The producers at the beginning of the Earth's food chain are plants.
