Hey, I need help with this question:

In the family tree below, people with the recessive trait of attached earlobes are shaded gray.

Step 1 review the imaginary strand of dna below. note the complementary base pairs. a g c a a t c c g t c t t g g t c g t t a g g c a g a a c c step 2 to begin replicating this strand of dna, draw the two sides of the strand separating. step 3 now, draw the free-floating bases linking up with the separate sides. remember to follow the rules of complementary base pairing. step 4 draw the two resulting dna strands.

Ascientist is conducting an investigation that involves water, silver, carbon dioxide, and oxygen gas which group of statements best describes all of the materials he is using in the investigation?