A rectangular lawn is 12.5 meters long and 4.8 meters wide. If a fence is built around this lawn, how long will the fence be? If 15 roses can be planted per square meter, how many roses can be planted in this lawn?
一个长方形草坪，长12.5米，宽4.8米．如果给这个草坪修一圈栅栏，那么需要多长的栅栏？如果每平方米可以栽15株月季花，那么这个草坪共可以栽多少株月季花？
<gadget id="calculator">12.5 * 4.8 * 15</gadget>
<output>900</output>

<result>900</result>