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+# Answers
+
+## Question 1
+
+Atomic variables are thread-safe variables provided by Java.
+
+They allow multiple threads to update a value safely without using synchronized blocks or locks.
+
+Regular variables do not provide this protection and may cause race conditions.
+
+## Question 2
+
+Four classes from the `java.util.concurrent.atomic` package are:
+
+- AtomicInteger
+- AtomicLong
+- AtomicBoolean
+- AtomicReference
+
+`AtomicInteger` is used for thread-safe integer operations such as incrementing or decrementing a counter.
+
+## Question 3
+
+Atomic variables are useful for simple operations on a single variable.
+
+For more complex operations involving multiple variables or multiple steps, locks are usually a better choice.
+
+## Question 4
+
+Yes. A program can be free of race conditions but still have poor performance.
+
+Too much synchronization, lock contention, and thread management overhead can slow down the program.
+
+## Question 5
+
+Adding more threads does not always improve performance because threads compete for CPU time and shared resources.
+
+In some cases, too many threads can actually reduce performance.
+
+## Question 6
+
+Deadlocks are difficult to detect because they depend on thread scheduling.
+
+A program may work correctly many times and then suddenly deadlock under different execution conditions.