At a game of billiards, A can give B 15 points in 60 and A can give C to 20 points in 60. How many points can B give C in a game of 90?	Choose the correct choice from the following answers.
A) 11 points  B) 12 points  C) 15 points  D) 10 points  E) 12 points
"A can give 15 points to B in 60".   =&gt; In a game of 60, A starts with 0 points where B starts with 15 points   "A can give 20 points to C in 60".   =&gt; In a game of 60, A starts with 0 points where C starts with 20 points   ie, in a game of 60-15-45, B can give C   20-15= 
<gadget id="calculator">  20-15</gadget>
<output>5</output>
5 points=&gt; ie, in a game of 90, B can give C 5×2=10 points   Answer is 10 points
<result>D</result>
At a game of billiards, A can give B 15 points in 60 and A can give C to 20 points in 60. How many points can B give C in a game of 90?