$408 × 30 = $
$508 × 30 = $
$508 × 50 = $
$507 × 90 = $
$705 × 90 = $
$602 × 40 = $
$206 × 80 = $
$305 × 50 = $
$305 × 20 = $
$109 × 20 = $
$407 × 60 = $
$501 × 70 = $
$709 × 30 = $
$406 × 60 = $
$506 × 60 = $
$504 × 60 = $
$109 × 60 = $
$501 × 40 = $
$102 × 20 = $
$203 × 30 = $
$702 × 20 = $
第34片

解析：这些题目都是基础的乘法运算题，主要考查学生乘法运算的能力。
答案：
$408 × 30 = 12240$
$508 × 30 = 15240$
$508 × 50 = 25400$
$507 × 90 = 45630$
$705 × 90 = 63450$
$602 × 40 = 24080$
$206 × 80 = 16480$
$305 × 50 = 15250$
$305 × 20 = 6100$
$109 × 20 = 2180$
$407 × 60 = 24420$
$501 × 70 = 35070$
$709 × 30 = 21270$
$406 × 60 = 24360$
$506 × 60 = 30360$
$504 × 60 = 30240$
$109 × 60 = 6540$
$501 × 40 = 20040$
$102 × 20 = 2040$
$203 × 30 = 6090$
$702 × 20 = 14040$

$0 × 775 = $
$0 × 852 = $
$0 × 900 = $
$0 × 104 = $
$0 × 0 = $
$0 × 145 = $
$1 × 998 = $
$841 × 0 = $
$214 × 0 = $
$414 × 0 = $
$500 + 0 = $
$619 + 0 = $
$0 + 118 = $
$196 - 0 = $
$0 × 111 = $
$111 - 0 = $
$2104 × 0 = $
$0 × 119 = $
$0 + 2024 = $
$0 ÷ 9 = $
$0 + 921 = $

解析：本题主要考查了乘法运算中与0和1相关的特殊性质，以及加法和减法运算中0的性质。具体来说，任何数与0相乘都等于0，任何数与1相乘都等于它本身，任何数加上或减去0都等于它本身，0除以任何非零数都等于0。
答案：
$0 × 775 = 0$
$0 × 852 = 0$
$0 × 900 = 0$
$0 × 104 = 0$
$0 × 0 = 0$
$0 × 145 = 0$
$1 × 998 = 998$
$841 × 0 = 0$
$214 × 0 = 0$
$414 × 0 = 0$
$500 + 0 = 500$
$619 + 0 = 619$
$0 + 118 = 118$
$196 - 0 = 196$
$0 × 111 = 0$
$111 - 0 = 111$
$2104 × 0 = 0$
$0 × 119 = 0$
$0 + 2024 = 2024$
$0 ÷ 9 = 0$
$0 + 921 = 921$

$120 × 30 = $
$210 × 30 = $
$307 × 40 = $
$307 × 50 = $
$310 × 90 = $
$220 × 80 = $
$230 × 90 = $
$430 × 50 = $
$440 × 60 = $
$540 × 50 = $
$170 × 60 = $
$180 × 30 = $
$330 × 60 = $
$440 × 70 = $
$230 × 50 = $
$460 × 80 = $
$280 × 50 = $
$630 × 30 = $
$201 × 50 = $
$504 × 50 = $
$203 × 50 = $

解析：这些题目都是基础的乘法口算题，考查的是学生对乘法运算的掌握程度。我们只需要直接计算出每个乘积即可。
答案：
$120 × 30 = 3600$
$210 × 30 = 6300$
$307 × 40 = 12280$
$307 × 50 = 15350$
$310 × 90 = 27900$
$220 × 80 = 17600$
$230 × 90 = 20700$
$430 × 50 = 21500$
$440 × 60 = 26400$
$540 × 50 = 27000$
$170 × 60 = 10200$
$180 × 30 = 5400$
$330 × 60 = 19800$
$440 × 70 = 30800$
$230 × 50 = 11500$
$460 × 80 = 36800$
$280 × 50 = 14000$
$630 × 30 = 18900$
$201 × 50 = 10050$
$504 × 50 = 25200$
$203 × 50 = 10150$