Answer:
I believe it would be these:
He can replace the 1.5-volt battery with a battery of higher voltage.
He can use a longer piece of wire that wraps more times around the bolt.
I'm not sure the others would work
Answer:
An example of mutualism is the relationship between remora and shark.
Explanation:
Remora depends on sharks for food and locomotion. It has a sucking mouth that helps it to attach itself to the shark.
Answer:
If the hydronium concentration increases, the pH decreases, causing the solution to become more acidic. This happens when an acid is introduced. As H+ ions dissociate from the acid and bond with water, they form hydronium ions, thus increasing the hydronium concentration of the solution.