Why is it necessary to avoid even traces of moisture during the use of a Grignard reagent?

To measure light intensity we use

A 0.8 m long solenoid has 800 turns and has a field density of 2.52 × 10^–3 T at its centre. What is current in the wire?

Consider the following reaction sequence

Product B is

Major product of the given reaction is

(CH₃)₃CBr + CH₃–CH₂–ONa → product

Chloroform on reaction with O₂ in presence of light gives