Hippos likely evolved from a group of anthracotheres about 15 million years ago, the first whales evolved over 50 million years ago, and the ancestor of both these groups was terrestrial. These first whales, such as Pakicetus, were typical land animals. They had long skulls and large carnivorous teeth. Hope I’ve helped ;)
<span>Answer: a. take place in nuclear reactors
</span><span>Controlled nuclear chain reactions are the reaction in nuclear reactors. The reaction is controlled to make its rate slower. This will make the reaction relatively safer, so the energy produced can be changed into electricity in power plant. When the reaction is not controlled, it could cause explosive like in nuclear bomb.</span>
The Vascular system transports water and sugars throughout the plant during photosynthesis.
The answer is Prokaryotes.