someone please help check my answers for the java questions?

True or false:

____True______ When the computer is turned off the information in primary memory (RAM) is lost.

____False______ Every if statement can have at most 1 matching else (ignore else-if statements).

____False______ Some Java variables can be used before declaring them.

____False_____ A control variable declared in a for loop header can be accessed after the loop is over.

____True______ A switch statement can use enum (enumeration) values as its case constants.

____True_____ A sentinel-controlled loop has to know in advance how many times to repeat.

____False______ A do-while loop may mistakenly be executed 0 times.