High risk & low risk of stock markets

The most common types of market risk include interest rate risk, equity risk, commodity risk, and currency risk. Interest rate risk covers the volatility that may accompany interest rate fluctuations and is most relevant to fixed-income investments. Equity risk is the risk involved in the changing prices of stock investments, and commodity risk covers the changing prices of commodities such as crude oil and corn. Currency risk, or exchange-rate risk, arises from the change in the price of one currency in relation to another. This may affect investors holding assets in another country.

Low risk

Treasury securities are investments offered by the U.S. government. These securities include Treasury bills, notes and bonds. ... These low-risk assets are guaranteed by the full faith and credit of the U.S. government, which means you are virtually guaranteed to be repaid.

giant impact theory - the moon was formed from the collision between earth and another mars-sized body.

colliding planetesimals hypothesis - the moon was formed from the same cloud of material as earth.

capture hypothesis - the moon was locked into orbit by earths gravity as it was passing by it.

accretion hypothesis - the moon was formed from collisions and combining of planetesimals.

i think this is right, if not and you know better let me know.