16-7= 9 you subtract the atomic number from the mass and get the number of neutrons so there ae 7 protons and 9 neutrons
"Exponential growth" means that the bigger it is, the faster it grows.
That's Choice 'D'.
Environmental scientists are using GPS ( It is effective but expensive) aerial monitoring (Quick but not the easiest), RFID tags, (mostly for long-term monitoring) and hidden cameras are used to study polar bear behavior without interruption to their environment.
Displacement is shortest distance from starting point, 4km.