Complementary strand of DNA?
DNA Strand 1: AATCGGTAC

TTAGCCATG

Explanation:

Deoxyribonucleic acid (DNA) is a double helix molecule made up of two complementary polynucleotide strands oriented antiparallel to each other. Each nucleotide in both DNA strands is composed of a five-carbon sugar (deoxyribose), a phosphate group and a nitrogenous base. In DNA, there are four types of nitrogenous bases: Thymine, Guanine, Adenine and Cytosine (in RNA, Uracil replace Thymine). According to the base-pairing rules, Adenine always pairs with Thymine through two hydrogen bonds, whereas Guanine always pairs with Cytosine through three hydrogen bonds.

b. the carbon cycle ensures living things have a source of hydrogen