Suppose a scientist discovers fossils of ancient horses in an area. The fossilized horses are much smaller than modern horses. They are found in the same layer as many fossilized tree trunks. Today, horses still live in the area, but it is now open grassland. How do you think the environment has changed over time, and how could this change have led modern horses to be larger than ancient horses?

About 3% of the water on earth is freshest. only about 40% of that freshwater is available for human use. why is so much freshwater unavailable for human use?

Answer asap need to be answered by wednesday morning explain how a buffer works, using an ethanoic acid / sodium ethanoate system including how the system resists changes in ph upon addition of a small amount of base and upon addition of a small amount of acid respectively. include the following calculations in your i. calculate the ph of a solution made by mixing 25cm3 0.1m ch3cooh and 40cm3 0.1m ch3coo-na+. [ka = 1.74 x 10-5 m] ii. calculate the ph following the addition of a 10cm3 portion of 0.08 m naoh to 500cm3 of this buffer solution. iii. calculate the ph following the addition of a 10cm3 portion of 0.08 m hcl to 200cm3 of the original buffer solution.

What is the formula of the ionic compound composed of calcium cations and chloride anions