一、口算。
$46 - 29 =$         $5×9 =$         $58÷8 =$
$8×6 =$         $51 - 17 =$         $37÷5 =$
$25 + 49 =$         $2×7 =$         $27÷3 =$
$7×7 =$         $32 + 29 =$         $18÷2 =$
$50 - 28 =$         $2×9 =$         $52÷7 =$
$4×4 =$         $43 + 48 =$         $36÷6 =$
$6×9 =$         $80 - 42 =$         $28÷4 =$
$66 - 38 =$         $2×8 =$         $56÷9 =$
$3×3 =$         $75 - 46 =$         $32÷8 =$
$35 + 33 =$         $5×6 =$         $44÷7 =$

$46 - 29 = 17$
$5×9 = 45$
$58÷8 = 7······2$
$8×6 = 48$
$51 - 17 = 34$
$37÷5 = 7······2$
$25 + 49 = 74$
$2×7 = 14$
$27÷3 = 9$
$7×7 = 49$
$32 + 29 = 61$
$18÷2 = 9$
$50 - 28 = 22$
$2×9 = 18$
$52÷7 = 7······3$
$4×4 = 16$
$43 + 48 = 91$
$36÷6 = 6$
$6×9 = 54$
$80 - 42 = 38$
$28÷4 = 7$
$66 - 38 = 28$
$2×8 = 16$
$56÷9 = 6······2$
$3×3 = 9$
$75 - 46 = 29$
$32÷8 = 4$
$35 + 33 = 68$
$5×6 = 30$
$44÷7 = 6······2$

二、下面物体的长度各是几厘米？填一填。

二、6   3   5