As you can see, there are numerous volcanic mountains in the pacific northwest. what is the most likely cause of the volcanic and earthquake activity in this region?

a. solar and lunar variations
b. rising and falling tides in the ocean
c. the differing climates of the mountain ranges
d. collision of tectonic plates

answer: you could do some invislibe ink.

explanation: i will tell you how to if u answer my question.

answer: atomic mass was originally used to arrange elements on the periodic table, but is no longer used to organize the modern version.

explanation:

originally atomic mass was used to arrange elements on the periodic table from left to right in a row. each column then shows similar properties of elements of a group.

in modern periodic table, the atoms are arranged in increasing atomic number. as atomic number represents the number of protons in an atom which is unique for every atom.