The half - life of carbon - 14 is 5,730 years. A fossil contains 25% carbon - 14 and 75% nitrogen - 14. How many half - lives have passed? A. 0
B. 1
C. 2
D. 3
E. 4​

What is the role of the ocular lens?

However, had it been a real sound, the sound's pitch would have been increased by the doppler effect, since the falcon was moving the source of the sound. perpendicular to away from towards at the same speed as

An object weigh 40n in air ,weigh 20n when submerged in water,and 30n when submerged in a liquid of unknown liquid density.what is the density of unknown of liquid?