Is a snowflake falling and then melting then getting condescend and then evaporates back into the air a example of the 3rd law of motion? PLEASE HELP:(

No no no. Newton's laws of motion are all about the relationship between forces and motions. That may be remotely connected with the falling and rising, but it has nothing to do with melting, condensation, or evaporation.

two charges are fixed in place on the x-axis as shown. the charge at x = 0 is negative and has magnitude q = 2 μcoulombs (1 μcoulomb = 10-6 coulombs). the charge at x = d, (d = +12 cm), is positive and has magnitude q = 4 μcoulombs. find a point x = xo along the x-axis at which the electric field is zero.