The half-life of Co-60 is 5.3 years. If the initial mass of the sample is 1000g, how much will remain after 15.9 years?

The twister and runaway train are two coasters at the same amusement park. both coasters start at the same height. the coaster for the twister is twice the mass of the coaster for the runaway train. which roller coaster has greater gravitational potential energy at the start of the ride?

The three types is stress that act on earths rocks are compression, tension, and

Is of of 3- ? a. 1--3- b. 1--2- c. 1--3- d. of