If Substance A has an LD50 of 20 mg/kg of body mass, and Substance B has an LD50 of 10 mg/kg of body mass, which substance is considered more deadly? Substance A is deadlier than Substance B.
Substance B is deadlier than Substance A
O Both substances are equally deadly enough to half a population
Neither of them are deadly because they do not reach at least 50 mg/kg

The embryos of a bird, a reptile, and a mammal are similar in appearance. how does comparing the physical appearance of embryos of different species support the theory of evolution? a. it shows that these organisms share a common ancestor. b. it provides evidence that these organisms eat the same foods.c. it shows that these organisms share the same habitat.d. it provides evidence that these organisms suffered a genetic mutation.