Mom goes to Suguo Supermarket to buy fruit, and the scales in the supermarket can weigh up to 8 kilograms. Mom first picks a few apples, and after weighing them, she finds that the pointer points to 2; she adds some more apples, and the pointer rotates 90 degrees clockwise. It is known that the apples are 2.5 yuan per kilogram, so how much does mother have to pay in total?
妈妈去苏果超市买水果，超市的台秤最多称8千克的物品．妈妈先挑了几个苹果，称量后发现指针指着2；她又添了一些苹果，指针顺时旋转了90度，已知苹果每千克2.5元，那么妈妈一共要付多少元．
<gadget id="calculator">90 / 30</gadget>
<output>3</output>

<gadget id="calculator">2 + 3</gadget>
<output>5</output>

<gadget id="calculator">2.5 * 5</gadget>
<output>12.5</output>

<result>12.5</result>