Mechanical, because the other two make no sense and mechanical energy is the combination of kinetic and potential energy, or moving and still respectively.
D is the only choice here that is appropriate given neutrons' lack of charge
1/32
Explanation it stated with half on 8 days then that means you divide 24 and 8 so its 3 and you have to multiply ✖ ½
1-PRIMARY ALKANOL 2-SECONDARY ALKANOL 3-TERTIARY ALKANOL