Based on fossil evidence about how long ago did the first single celled life form appear on earth

What function does a limb serve in each animal how are the limb bones of the four animal similar based on the similarities what can be inferred about the evolution of the poor animals

Ascience research group is testing a new type of plant food. one trial is conducted in a controlled experiment. the data from the trial show that the plant that received the new food grew faster than the control plant. the group announces that the new plant food makes plants grow faster. what is the main weakness in this scientific claim?

Produce proteins by following coded instructions that come from the nucleus of the cell.