What are the three waste materials that the lungs excrete?

How do you transfer mrna into codons ? i'm so confused : (

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?

Aparent with freckles is crossed with a parent without freckles. the punnett square shows the possible genotypes and phenotypes of the offspring. which statement accurately describes the probability of phenotypes? a.the offspring are more likely to have freckles. b.the offspring are more likely to have no freckles. c.the likelihood of the offspring having freckles and not having freckles is the same. d.the likelihood of the offspring having freckles and not having freckles cannot be determined.