Alysha wants to test the effect of different materials on the melting rate of ice. She finds the initial mass of four pieces of ice. She then covers three pieces with either tinfoil, plastic wrap, or paper. The fourth piece is left uncovered.
After 30 minutes, Alysha calculates the final mass of each piece of ice to determine which melted the fastest.
What are the independent and dependent variables in Alysha's experiment?

a) The dependent variable is the type of cover material, and the independent variable is the mass of the ice.
b) The dependent variable is the mass of the ice, and the independent variable is the time the ice takes to melt.
c) The dependent variable is the mass of the ice, and the independent variable is the type of cover material.
d)
The dependent variable is the time the ice takes to melt, and the independent variable is the type of cover material.

You will create a molecular clock model for an arthropod gene. follow these guidelines to make your model: . your timeline will span from 90 million years ago to the present. the common ancestor in your model is an arthropod that lived 90 million years ago. the gene that you'll track codes for a protein in the species venom . the dna sequence youll track contains 10 nitrogen bases. you can choose the order of the bases and where the mutations occur. this gene mutates at a rate of approximately 0.76 base pairs every 17.1 million years. to build your model,/ calculate the estimated time period it takes for 1 base pair to mutate. the first time period will only show the common ancestor. at the beginning of the second time period, three lineages will diverge from the common ancestor, each with a different mutation in their gene sequences. the first and third descendant species will survive for the rest of the timeline. the second descendant species was extinct 50 million years ago. calculate how long it will take for one full base pair mutation to occur. explain your reasoning by constructing a mathematical equation