在下列元素中,那项被用作原子量测量的新的国际标准()。
A. 1H
B. 19F
C. 40Ca
D. 16O
E. 12C
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Tenor is concerned with the purpose and subject-matter of communications.()
.initiative is a negative feeling.()
The more lovely a musical piece sounds, the more value it has.()
American food is tasteless and innutritious.()