I am quite sure the first one is Friction, but I am not sure about the second one. Is it wind?
The correct answer is A. Installation of rigid metal conduit requires grounding and the grounding equipment used may weaken the structure.
Answer:
Robert Oppenheimer made the first atomic bomb.
I think god did ??? I searched it up okay
Answer: bismuth and nitrogen, because they have the same number of valence electrons
Explanation:
Elements are distributed in groups and periods in a periodic table.
Elements that belong to same groups will show similar chemical properties because they have same number of valence electrons.
The number of valence electrons in Bismuth and nitrogen are 5 and thus thus they will show similar chemical properties and thus belong to the same group.
The atomic masses of elements in a group will differ drastically.
The group number has got nothing to be the isolation year.
Thus bismuth and nitrogen belong to same group because they have the same number of valence electrons