Considering the structure of double stranded DNA, what kinds of bonds hold one complementary strand to the other?

What is the name for a substance formed in a chemical reaction

In tomato plants, mendel found that the allele for smooth seeds (s) is dominant, while the allele for wrinkled seeds (s) is recessive. which of these punnett squares shows crosses between two plants heterozygous for smooth seeds? i need this to be answered as soon as ! sry the picture is bad quality

This is collection of data made by comparing objects in standard units. in science, the units are metric.