Grignard reagents add to carbonate esters as they add to other esters. (a) Predict the major product

Question:

Grignard reagents add to carbonate esters as they add to other esters.
(a) Predict the major product of the following reaction.

(b) Show how you would synthesize 3-ethylpentan-3-ol using diethyl carbonate and ethyl bromide as your only organic reagents.
(c) Diethyl carbonate is a liquid reagent that is easy to handle. In contrast, phosgene is a highly toxic and corrosive gas.
Show how you might use diethyl carbonate instead of phosgene to make Lexan®. Also show how you might use diethyl carbonate instead of methyl isocyanate to make Sevin® insecticide.