Cho hình chóp $S.ABCD$có đáy ABCD là hình thoi cạnh bằng 1, góc $\widehat{ABC}={{60}^{0}}$. Cạnh bên $SD=\sqrt{2}$. Hình chiếu vuông góc của S trên mặt phẳng $\displaystyle (ABCD)$ là điểm H thuộc đoạn BD sao cho $HD=3HB$. Tính thể tích khối chóp $S.ABCD$
A. $V=\frac{\sqrt{5}}{24}$
B. $V=\frac{\sqrt{15}}{24}$ 
C. $V=\frac{\sqrt{15}}{8}$ 
D. $V=\frac{\sqrt{15}}{12}$

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Read the following passage and choose the best answer for each blank: 
          Students who attend the Scottish Universities can do an ordinary degree in three years, (1)_________ complete an honour degree in four years. There are also sandwich courses in (2)_________  the student may need to do a year more. The sandwich courses (3) ___ work placement which (4)_____ the students to work for a short period of time before they complete their courses. Scottish universities tend not to specialise subjects (5)____ the third year when students may decide to complete an ordinary degree in a (6) ______ year or embark on a two-year honour course. Most universities award a Bachelor Degree to the students who have completed their undergraduate courses (7)________  for historical reasons, the Scottish ancient universities award a Master of Arts (MA) degree to arts students who have completed their undergraduate courses. These MA degrees are (8)________ to a Bachelor Degree. Honour degrees are usually split into classes: first class (I), upper second class (II :1), lower second class (II :2) and third (III), and unclassified (below third class). Students who apply (9)______ a Scottish University while attending a Scottish secondary school (10)_______ not need to pay for university tuition fees as it is paid for on their behalf by the Student Awards Agency for Scotland.
 
1. A. and              B. nor                 C. or                D. either2. A. which           B. that                C. where.        D. whom3. A. invite           B. please            C. offer            D. display4. A. lets              B. opens             C. allows.        D. suggests .5. A. once            B. until                C. after            D. soon6. A. further         B. farther            C. better          D. higher7. A. despite        B. in spite           C. but               D. though8. A. equivalent    B. same             C. familiar          D. comparative9. A. to                B. for                  C. in                  D. with10. A. are            'B. may               C. do                 D. must
A. 1. C                2. A                      3. C                       4. A                    5. B6. A                7. B                      8. D                       9. B                    10. A
B. 1. C                2. A                      3. C                       4. C                    5. B6. A                7. D                      8. A                       9. B                    10. C
C. 1. D                2. A                      3. C                       4. C                    5. D6. B                7. B                      8. D                       9. C                    10. A
D. 1. C                2. D                      3. C                       4. A                    5. B6. A                7. D                      8. D                       9. C                    10. A