Sulphur Trioxide

Q. How many sigma and pi bonds will form when one s-orbital undergo head-on overlapping with one p-orbital?

Q. In the gaseous phase, the sigma O – S – O bond angle in the $S{O}_3$ molecule is degrees.

Q. <!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}--> Which of the following hydrocarbon can undergo addition reaction?
<!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}--> ${\text{CH}}_4$ , ${\text{C}}_2$${\text{H}}_6$, ${\text{C}}_2$${\text{H}}_4$ , ${\text{C}}_3$${\text{H}}_6$

Q. <!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}--> Which of the following hydrocarbon can undergo addition reaction?
<!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}--> ${\text{CH}}_4$ , ${\text{C}}_2$${\text{H}}_6$, ${\text{C}}_2$${\text{H}}_4$ , ${\text{C}}_3$${\text{H}}_6$