The shark and remora have a relationship that benefits the remora but neither helps nor harms the shark What type of relationship is this

Commensalism
Elicit from students that the shark and the remoras, the smaller fish below the shark, have a symbiotic relationship called commensalism, where the remoras benefit from holding onto the shark, but neither species is harmed.

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 correct answer is weight.