Syntax defines the rules by which a program must adhere to be processed by the compiler. Semantics defines the logical rules that make a computer program do what you want it to.
A3:
Computers represent data as a sequence of 1s and 0s.
A4:
A data type is a human-readable tag that represents a specific usage of a computer's memory.
A5:
A short is represented by two bytes while an int is represented by four bytes.
A6:
The first two statements are legal but the third is not because the result of adding two shorts is automatically converted to an integer; an explicit cast to a short is required for this statement to be correct:
short result = ( short )( s1 + s2 );
A7:
Arithmetic promotion means that a variable of a certain data type is automatically converted to a "wider" type during an arithmetic operation.
A8:
You can only assign a byte or a short to a short.
A9:
Casting is explicitly interpreting a variable as a more narrow type; the result of this is dropping bits from the variable. It is accomplished by prefacing the variable with the type to cast the variable to enclosed in parentheses:
int integer = 50; short s = ( short ) integer;
A10:
You define a variable to be a constant by prefacing its data type with the keyword final: