how to conclude that the given reaction proceeds in sn1/sn2/e1/e2 mechanism?

E1 and reaction proceed through formation of common inintermediate.E1 reactions of a word with substrates that can form stable Carbo cationsi.e.tertiary halides, they are also favoured by use of poor nucleophiles and generally favoured by use of polar solvents.in most Uni molecular reaction SN1 reaction favour over even especially at low temperature and on increasing the temperature of reaction it`s favours E1 mechanism.if strong bases added then reaction force and E2 reaction to take place instead.mainly eat 2 and SN2 reaction occur simultaneously.use all strong ,slightly polarizable base such as alkoxide ion( especially hindreed once) tend to increase E2 . use of weak base ion such as chloride ion increase SN2 reaction.if we use strong sterically hindered base such as tert butoxide ion then E2 is more favoured then SN2.elimination reactions have greater free energy of activation then substitution reactions because more bonding changes occur during elimination.

Sorry some correct iin in above answer. In first line E1 and SN1.In second line instead of word it is occur.