1. $85047
2. $113,080
3. $ 75,820
4. $41595
Explanation:
Lodestone am iron were the only known magnetic materials in Gilbert's day, and his task was to investigate magnetism. Gilbert was so sure that the earth was a giant lodestone and used the earth as a primary reference, defining the north(magnetic) pole of a needle, or a a nail floating on a piece of cork, to be that which turns towards the Earth's north geographic pole. he wanted to prove this with a model Terella, using short pieces of iron.
Answer:
For the first one its about 25 feet
Explanation:
We use the following formula to determine our acceleration:

We normally use letters in this formula, which gives us:

Filling in this formula gives us:
Δv (change of velocity) = 12 - 4 = 8 m/s
t = 1s

So our answer: the acceleration is