The answer is #4. The first and second one involve acid, which is chemical weathering. The third one involves oxidation, which is a chemical process. The only mechanical process is option four.
Your blood vessels dilate which is called vasodilation, this allows your blood to carry out the excess heat from inside your body to the outside.
Answer:
In the explanation. :)
Explanation:
Human powered generators are the best source for the rescue team. We cannot always depend on the sun. What if the sun is not out that day? What if it's a rainy day? What if the sun is what's causing the rescue team to come out? Human powered generators are sometimes untrustworthy, but at the same time we know that at least it's a step away. We don't have to wait all-day for the sun to help out. Of course, the energy from the sun is always going to be there and won't cause anybody hurt, harm, or danger, but at the same time we can always convert to human powered generators and they'll work just as perfect.
Hope this helps, have a great day!