1. DrawtheLewisstructureforammonia, CH​4.​ 2. Draw the Lewis structure for hydrogen sulfide, C​2H​4.​

3. Draw the Lewis structure for phosphorus trifluoride, C​2H​2.​

4. Draw the Lewis structure for carbon dioxide, CH​3O​H.

Ais your answer to this

Ch4 and ph3 are both covalent since they are composed both of non-metals.    ch4 is non- polar because of  london forces and has a geometry of tetrahedral  ph3 , on the other hand, is umbrella shaped polar and has dipole-dipole intermolecular force (imf) . since ph3 is polar, it has a stronger imf   

The population of unionid mussels decreased after zebra mussels were introduced. zebra mussels competed with the unionid mussels for food. the zebra mussels were able to displace the unionid mussels, allowing the zebra mussel population to increase  over the years. the unionid mussel population decreased because  of lack of food.