What do arrows indicate about the flow of energy through a community

The activity of the modern sample is 1.10 bq . how long does that measurement take?

Photosynthesis uses co2 and cellular respiration produces co2. we call the point when the two processes are in balance--when there is no net production of co2--the compensation point. how might you limit one of the processes in order to achieve a compensation point?

In which way are mercury and venus similar? they both rotate from east to west. they are both small and rocky. they both have thick atmospheres. they both are similar to earth in structure.