Write the structure(s) of the major product(s) that you expect from each of the following electrophilic aromatic substitutions. 

(a) Nitration of methylbenzene (toluene); 

(b) sulfonation of methylbenzene (toluene); 

(c) nitration of 1,1-dimethylethylbenzene (tert-butylbenzene); 

(d) sulfonation of 1,1-dimethylethylbenzene (tert-butylbenzene). In what way does changing the substrate structures from methylbenzene (toluene) in (a) and (b) to 1,1-dimethylethylbenzene (tert-butylbenzene) in (c) and (d) affect the expected product distributions?