It means it is 14 k gold.
The number "928" on your gold necklace is likely a marking to indicate the gold purity, which is usually measured in karats. In this case, "928" likely means that the necklace is 22 karat gold, indicating that it is made up of 91.6% pure gold.
It most likely means the percentage of gold in the material.
It is a reflective plastic wrap. Mylar plastic coated with gold was used to reflect solar radiation that would otherwise overheat the spacecraft body. Gold-mylar film reflects both visible and infrared radiation.
It most likely means the percentage of gold in the material.
THF (tetrahydrofuran) is the most typical solvent for Mylar.
928 =92800%
928/1
It is: 928 = CMXXVIII
928 / 2 is equal to 464.
Mylar is a type of strong thin polyester that is used most notably in Mylar ballons, but is also used at certain tapes, fabric, and insulating sheeting.
54.5882