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docs/lessons/offset-image/quiz-answers.md

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+# offset image quiz answers
+
+shift an image horizontally across the display with offset #offset #screen  #variables #docs
+
+This is the answer key for the [offset image quiz](/microbit/lessons/offset-image/quiz).
+
+## 1. What is a 'if, then, else statement' ? 
+
+<br/>
+
+An if-then statement will run a block of code if the condition specified is true. The statement will run the "else" block of code if that condition is false.
+
+## 2. Consider the message
+
+Write the line of code that that will create the message "Push button A" (Hint: This message appears `if` the offset is equal -4 then the BBC micro:bit will state "Push Button A").
+
+<br/>
+
+```
+if (offset == -4) {
+    basic.showString("Push Button A", 150)
+}
+```
+
+## 3. Consider the following image
+
+![](/static/mb/lessons/offset-image-0.png)
+
+When with this image be displayed?
+
+<br/>
+
+When the offset is NOT equal to -4 then the BBC micro:bit will show the image above.
+
+## 4. Consider the following image
+
+![](/static/mb/lessons/offset-image-1.png)
+
+Write the two lines of code that cause the `variable` offset to increase by one when button `A` is pressed.
+
+<br/>
+
+```
+input.onButtonPressed(Button.A, () => {
+    offset = offset + 1
+})
+```
+