杨小奇做了两块三角板，如果它们的三个内角分别是90°、75°、15°和90°、54°、36°，那么用这两块三角形可以画出（ ）个互不相等的锐角．
A．30
B．29
C．10
D．9
用三个内角分别是90°、75°、15°和90°、54°、36°的三角板可以画出最小角是：
54°-36°-15°=3°，
两个三角板内角度数都是3的整数度，
即可知在锐角范围内，只要是3的倍数的锐角都可以画出，
在锐角范围内3倍数最大锐角为87°，
3°、6°…87°共有29个3的倍数的锐角，
故选B．
There is a poster below. Read it carefully. VISIT SWANSEA ZOO! Come and see the African elephants and the new tigers from India. The Arctic bears are waiting to meet you, and the monkeys from Zaire are waiting to throw things at you. The hyenas (a flesh-eating animal, like a wolf, with a howl that sounds like wild laughter) from Tanzania are waiting to laugh at you, and the giraffes from Zambia are waiting to look down on you. Tickets Adult: $1.20 Children: Over 12: 80 cent Under 12 : Free Opening Time: 9: 00a. m. ~4: 00p. m. Except Fridays: 10: 00a. m. ~3: 00p. m. KEEP THE ZOO CLEAN! DO NOT FEED,TOUCH OR GO NEAR THE ANIMALS! 小题1:If you want to visit the Swansea Zoo, what is the best time to go there?
much should you pay?
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