What is A (capitalized A on the left)?

Idon’t understand this page, can someone ?

Which of the following best explains why the end of a spoon sticking out of a cup of hot water also gets hot? question 7 options: the heat from the hot water is conducted through the spoon handle the hot water heats the air surrounding the upper part of the spoon. the hot water causes a physical change in the spoon handle. the hot water causes a chemical reaction to take place in the spoon.

One nanometer is equal to how many meters?