程序填空题：补充完善如下代码，使得程序能够计算 a 中各元素与 b 逐项乘积的累加和。提示代码如下：a = [[1,2,3], [4,5,6], [7,8,9]]b = [3,6,9]____①____for c in a:for j in ____②____:s += c[j]*b[j]print(s)
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In most cases, lung cancer is _________ to cigarette smoking.
A. related
B. contacted
C. joined
D. united
Itruly believe we must speak out and _________ our voice heard at this very moment.
A. do
B. make
C. declare
D. repeat
One morning the teacher allowed __________.
A. him to go
B. he goes
C. him go
D. him going
Her neighbors used to hear her ________ in the garden.
A. to sing
B. sang
C. to have sung
D. sing
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