18: D, homologous
20: B, DNA
I can’t see 17 or 19!
Very True , solar energy is used for producing solar energy, it is also used for drying clothes.<span>Active solar energy uses electrical technology and mechanical technology like collection panels in capturing, converting and storing energy.</span>
Through a sequence of steps called the immune response<span>, the </span>immune system<span>attacks these </span>pathogens<span>. ... This is the </span>immune system<span>. Cells. The cells involved are white blood cells (leukocytes), which seek out and destroy disease-causing organisms or substances</span>
The answer is B cell wall
