If you start with one gram of pure 14C half-life 6000 years, the ...

[renzo156]

If you start with one gram of pure 14C half-life 6000 years, the amount remaining after 36,000 years will be
 
  A) 1/32 gram. B) 1/64 gram. C) 1/128 gram. D) 1/6 gram. E) None.

Question 2

In order to simulate apparent weightlessness for astronauts in training (when the astronauts do not push on a seat), they are flown in a vertical circle.
 
  If the passengers are to experience weightlessness, how fast should an airplane be moving at the top of a vertical circle with a radius of 2.5 km? A) 79 m/s
  B) 310 m/s
  C) 260 m/s
  D) 160 m/s
  E) 510 m/s

[blakeserpa]

Answer to Question 1

B

Answer to Question 2

D

[renzo156]

TYSM

[nyrave]

Gracias!