The diagram below shows a portion of the geologic time scale. Based on the time scale, it can be concluded that a flowering plants appeared on Earth before animals.
b animals appeared on Earth before flowering plants.
c flowering plants created the first oxygen molecules.
d land animals created the first oxygen molecules.

brain development. a child's brain undergoes an amazing period of development from birth to three—producing more than a million neural connections each second. the development of the brain is influenced by many factors, including a child's relationships, experiences and environment.

explanation:

measuring light intensity

light meters can be used to measure light intensity. the meter is held at the soil surface and pointed in the direction of the maximum light intensity, and then the meter is read.

errors can be made when measuring light intensity by accidentally shading the light meter. the reliability of the results can be checked by taking many samples.