Answer
Carbonic acid: $H_{2}CO_{3}$
Lithium hydroxide: $LiOH$
Lithium carbonate: $Li_{2}CO_{3}$
Work Step by Step
Carbonate anion $CO_{3}^{2-}$ has a -2 charge, hydrogen ion has a +1 charge. In order to balance charges and form carbonic acid 2 hydrogen ions are required. Thus, the chemical formula will be $H_{2}CO_{3}$
Lithium ion has a +1 charge ($Li^{+}$) and Hydroxide ions have a -1 charge ($OH^{-}$). Since these charges are balanced, the chemical formula for lithium hydroxide will be $LiOH$
Lithium ion has a +1 charge ($Li^{+}$) and carbonate anion has a -2 charge $CO_{3}^{2-}$. In order to balance charges, 2 lithium ions should be present. The formula will then be $Li_{2}CO_{3}$