对二次曲面,下列说法不正确的是().<img src="https://zk.995w.com/lqwvjeImg/a1/a19eaaaf272b94498cc7597c53b69f5e.png"style="width:27px;height:20px;">方程<img src="https://zk.995w.com/lqwvjeImg/88/88583b77ad0d06297d31ade30e39680b.png"style="width:83px;height:23px;">表示椭圆抛物面<img src="https://zk.995w.com/lqwvjeImg/9c/9c8d2664999280212b251b403b443e5c.png"style="width:27px;height:20px;">方程<img src="https://zk.995w.com/lqwvjeImg/65/656c66d59016bfdfafcfed207b03eda2.png"style="width:111px;height:23px;">表示椭球面<img src="https://zk.995w.com/lqwvjeImg/c5/c505ca97495587e508a6b414209b09fe.png"style="width:27px;height:20px;">方程<img src="https://zk.995w.com/lqwvjeImg/6d/6d453fbc9a85c8ca8c870c95a8931443.png"style="width:48px;height:24px;">表示抛物柱面<img src="https://zk.995w.com/lqwvjeImg/c5/c52e875e9253d51ab7c82824501773b2.png"style="width:28px;height:20px;">方程<img src="https://zk.995w.com/lqwvjeImg/f7/f753b8f6ffe887e4209337cf288f6250.png"style="width:120px;height:36px;">表示双叶双曲面<br>·方程<img src="https://zk.995w.com/lqwvjeImg/56/5614dff66391ffe222962cb09ebf4503.png" 表示椭球面<br>·方程<img src="https://zk.995w.com/lqwvjeImg/c5/c5f5d1a64da3eb0df0dec55d45efc4ae.png" 表示抛物柱面<br>·方程<img src="https://s3.cn-north-1.amazonaws.com.cn/qingshuxuetang/uploadFile/photo/1681886203003_a67d1ad75893405fad9347d3cdd96112.png" 表示双叶双曲面

对二次曲面,下列说法不正确的是().