Base pairs.
Four + Five = Nine
The third letter in base is S.
IT ADDS UP.
Answer:
Option D, Index fossil helps scientists to determine the relative ages of rocks by their positions
Explanation:
Index fossils are arranged in layer in such a way that the lowest layer represent the oldest fossil and the top most layer represents the youngest fossil. Scientist use this concept to determine the relative age of the rocks based on their position beneath the earth’s surface
Hence, option D is correct
Atomic number = amount of protons, so 7 protons.
Because it is a neutral atom, that means that the number of protons has to be the same as the number of electrons. So, there are 7 electrons.
The mass number of an atom, 15, is the total number of protons + neutrons, so 15 - 7 = 8. There are 8 neutrons
Answer:
Sun
Explanation:
Every day, many amounts of water evaporate from lakes and rivers, by heat energy from the sun.