balancing other equations?

Question

help balance the following:
3)___K + ____B2O3 ---> K2O + __B

4) __HCl +___ NaOH ---> NaCl + ___H2O

5)___Na + ___NaNO3 ---> ___Na2O + ___N2

6) ____C + ____S8 ---> _____CS2

Answer 1

3. 2K+B2O3---> K2O+2B I think?

4. __HCl +___ NaOH ---> NaCl + ___H2O -Already balanced

5.__Na + ___2NaNO3 ---> ___3Na2O + ___N2

6.____4C + ____S8 ---> _____4CS2

Answer 2

6 1 3 2
1 1 1 1
10 2 6 1
4 1 4

Look for the rare elements, like on the 5) I balanced N first.