There are 4 kinds of apple trees in an apple orchard, each with 3 rows, and each row has 12 trees. How many apple trees are there in this orchard?
苹果园共有4种苹果树，每种有3行，每行有12棵．这个果园共有苹果树多少棵？
<gadget id="calculator">3 * 12 * 4</gadget>
<output>144</output>

<result>144</result>