Khoảng cách giữa 2 nguyên tử C - C trong C2H6, C2H4, C2H2 tương ứng (Å) là: 1,54; 1,35; 1,21. Vậy bán kính cộng hóa trị Å của C là

2positives of biotechnology: 1. plants have become more resistant to viruses and other communicable pests.2. with the of biotechnology, we have been able to produce better tasting fruits as well as vegetables.2 negatives of biotechnology: 1. biotechnology poses a number of environmental threats. genetically modifies crops often infect monarch butterflies and other insect species.2. viruses could combine with crops.