It is known that ∠1 and ∠2 are two acute angles in a right triangle. If ∠1=48°, then ∠2=how many.
已知∠1和∠2是直角三角形中的两个锐角，如果∠1=48°，那么∠2=多少．
<gadget id="calculator">90 - 48</gadget>
<output>42</output>

<result>42</result>