13.
如图,正方形ABCD的对角线AC与BD相交于点O,∠ACB的角平分线分别交AB、BD于M、N两点,若AM=2,则正方形的边长为( )
| A. | 4 | B. | 3 | C. | 2+$\sqrt{2}$ | D. | $\sqrt{2}+1$ |
11.
如图,正八边形ABCDEFGH内接于圆,点P是弧GH上的任意一点,则∠CPE的度数为( )
0 282330 282338 282344 282348 282354 282356 282360 282366 282368 282374 282380 282384 282386 282390 282396 282398 282404 282408 282410 282414 282416 282420 282422 282424 282425 282426 282428 282429 282430 282432 282434 282438 282440 282444 282446 282450 282456 282458 282464 282468 282470 282474 282480 282486 282488 282494 282498 282500 282506 282510 282516 282524 366461
| A. | 30° | B. | 15° | C. | 60° | D. | 45° |