Answer
The bond polarities of SiH4 are polar, the molecular shape is tetrahedral, and the molecule is nonpolar.
Step-by-step explanation
The bond polarities of SiH4 are polar, this is because of the strong electronegativities difference in the bond that exists between Silicon and Hydrogen.
The molecular shape is tetrahedral, because of the same symmetric charge distribution around them.
The molecule is nonpolar because the net four S-H bonds dipole moments are zero.