14.设抛物线y2=16x的焦点为F,点P在此抛物线上,且横坐标为5,则|PF|等于( )
| A. | 13 | B. | 8 | C. | 9 | D. | 10 |
11.已知四棱锥P-ABCD的三视图如图所示,则此四棱锥的表面积为( )

| A. | $\frac{7+2\sqrt{2}+\sqrt{5}}{2}$ | B. | $\frac{3+2\sqrt{2}+\sqrt{6}}{2}$ | C. | $\frac{7+2\sqrt{2}+6}{2}$ | D. | $\frac{3+2\sqrt{2}+\sqrt{5}}{2}$ |
6.若抛物线y2=2mx(m>0)上的点,M(3,y0)到焦点的距离是5,则y0等于( )
0 224285 224293 224299 224303 224309 224311 224315 224321 224323 224329 224335 224339 224341 224345 224351 224353 224359 224363 224365 224369 224371 224375 224377 224379 224380 224381 224383 224384 224385 224387 224389 224393 224395 224399 224401 224405 224411 224413 224419 224423 224425 224429 224435 224441 224443 224449 224453 224455 224461 224465 224471 224479 266669
| A. | 2$\sqrt{3}$ | B. | 6 | C. | ±2$\sqrt{6}$ | D. | ±$\sqrt{15}$ |