You need a 450 microgram sample of gold, but you only have a mass balance that measures in decigrams. Convert the amount of gold you need to decigrams by comparing the exponents. Provide your answer in scientific notation. Be sure to show your work.

it's when something is going so fast it makes a loud noise, breaking the sound barrier, for example: a jet makes a loud noise, not only cause of the jet but because they reached a point where they went so fast that you can year the noise from various parts, kinda like a police car, lets say the car was going   so fast that you hear the siren of the cop car right next to you, but the car is probably a mile a way, it's cos the siren was next to you a few seconds if you understand me

there are no contact forces mentioned on the list of choices that you've provided.