When did the first multicellular organisms appear?

Why is taking care of yourself a time management techique

Approximately what wavelength of light is best absorbed by chlorophyll a

Ascientist is designing an investigation to study the impact of invasive bird populations on local, native bird populations at backyard bird feeders. what population is most likely to be a control group for the investigation? amount of food number of bird feeders invasive bird populations local backyard birdfeeders without food