15.
如图,已知长方体的长宽高分别为4、2、1,一只蚂蚁沿长方体的表面,从点A爬到点B,最短路程为( )
| A. | $\sqrt{29}$ | B. | $\sqrt{37}$ | C. | $\sqrt{21}$ | D. | 5 |
10.
如图,△ABC是⊙O的内接三角形,∠AOB=135°,则∠ACB的度数为( )
0 282129 282137 282143 282147 282153 282155 282159 282165 282167 282173 282179 282183 282185 282189 282195 282197 282203 282207 282209 282213 282215 282219 282221 282223 282224 282225 282227 282228 282229 282231 282233 282237 282239 282243 282245 282249 282255 282257 282263 282267 282269 282273 282279 282285 282287 282293 282297 282299 282305 282309 282315 282323 366461
| A. | 35° | B. | 55° | C. | 60° | D. | 67.5° |