4. The range of wavelengths of light that is visible to humans is
A. 380 nm - 550 nm
B. 400 nm - 600 nm
C. 380 nm - 750 nm
D. 200 nm - 900 nm

Genetic disorders can result when sister chromatids fail to seperate properly. during what phase is this problem most likely to occur?

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?

Which of the following is a reason why early living organisms on earth could not have survived on the surface? 1. the lack of an ozone layer 2. the lack of oxygen in the atmosphere 3. the fact that these organisms were single-celled