Problem page the half life for the radioactive decay of rubidium- to strontium- is years. suppose nuclear chemical analysis shows that there is of strontium- for every of rubidium- in a certain sample of rock. calculate the age of the rock. round your answer to significant digits

You are traveling in a car going at a constant speed of 100km/h down a long, straight highway. you pass another car going in the same direction which is traveling at a constant speed of 80km/h. as measured from your car's reference frame this other car is traveling at −20km/h. what is the acceleration of your car as measured from the other car's reference frame? what is the acceleration of the other car as measured from your car's reference frame?