如图,AB为⊙O直径,CD⊥AB,∠BDC=35°,则∠CAD=____
化简:4x2xy÷12x3·3y
24÷3____2×2 21÷7____24÷6 45÷9____35÷5
2×3____54÷9 81÷9____18÷9 4×6____24÷3
____?