I think the correct answer is the first option. It has nonpolar bonds and a symmetrical structure. The structure of a BF3 molecule shows a symmetrical trigonal geometry. The net dipole moment of the molecule is zero therefore it is polar.
Hello, here’s the answer to your question. Converting ammonia to nitrate, which is absorbed by plants
I don't know this article, but I do know some major changes: first, the change from the plum pudding model (no nucleus, just electrons) to the gold foil experiment, which had Rutherford shoot alpha particles at a sheet of gold only to find them rebounding, proving the existence of a positively charged mass, i.e a nucleus, in the atom. However, this changed again when Bohr realized that the negatively charged electrons should be attracted to the positively charged center, so that there must be something else inside the nucleus.
The answer is 3. As 5 * 3 = 15.
Is there any other equations I may be able to help you with? :)