Answer: the four terrestrial planets must once have been hot enough to be molten (like a liquid)
Explanation: Terrestrial planets can be defined as any planet of the solar system or any exoplanet which is "Earth-like" in the sense that it is composed primarily of metals and rock, in contrast to a planet which is a gas giant.
Within the Solar System, the terrestrial planets are the inner planets closest to the Sun, i.e. Mercury, Venus, Earth, and Mars.
Scientist believing that the densest, heaviest materials are at the center and not evenly distributed can be due to the fact that they must once have been hot enough to be molten. In this case, density will take place, making the heavier under and the lighter on top.
Answer:
An increase in the supply of money works both through lowering interest rates, which spurs investment, and through putting more money in the hands of consumers, making them feel wealthier, and thus stimulating spending. Business firms respond to increased sales by ordering more raw materials and increasing production.
Explanation:
Money supply and interest rates have an inverse relationship. A larger money supply lowers market interest rates, making it less expensive for consumers to borrow. Conversely, smaller money supplies tend to raise market interest rates, making it pricier for consumers to take out a loan.
Explanation:

<em><u>Bitcoin is a digital currency which operates free of any central control or the oversight of banks or governments. Instead it relies on peer-to-peer software and cryptography. A public ledger records all bitcoin transactions and copies are held on servers around the world</u></em>
Answer:
D-Piedmont
Explanation:
It is situated between the Atlantic coastal plain and the main Appalachian Mountains, stretching from New York in the north to central Alabama in the south.