Please answer 8,9, and 10 for 20 points plus brainliest :) link=reported, those dont help

Which skill, if it cannot be performed by a 3-year-old child, should alert the nurse that the child may be developmentally delayed?

How can scientists test their ideas about the origin of the universe if they can't physically interact with or study?

How does the molecular clock work? a. it analyzes the brain functionality of two different species.b. it examines and compares the physical characteristics of two different species.c. it illustrates relationships between two different species.d. it compares the number of mutations that exist in the dna of two different species.