Renewable resources are often grouped into one category because they have one thing in common. What do they have in common? A) They are all renewable. B) They all come from the Sun's energy. C) They all are expensive resources that are commonly used D) They all are technologically inaccessable.

The gene that causes sickle-cell disease is present in a higher percentage of residents of sub-saharan africa than among those of african descent living in the united states. even though this gene causes sickle-cell disease, it also provides some protection from malaria, a serious disease that is widespread in sub-saharan africa but absent in the united states. discuss an evolutionary process that could account for the different percentages of the sickle-cell gene among residents of the two regions.

20 points and brainlist 1. london has suffered from terrible air pollution for at least seven centuries. why is the city so prone to its famous “london fog? ” what did london do to get rid of its air pollution? 2. why does air pollution cause problems in developing nations more than in developed ones?

Which measurement unit represents volume? liter kilometer square centimeter centigram