An isotope has a half-life of 2.4 days. How many half-lives have passed if you measure the activity after 9.6 days?

Which statement best describes the relationship between an allele and a gene? question 1 a. an allele is a variation of a gene that can be expressed as a phenotype. b. an allele is the part of a gene that attaches to messenger rna molecules. c. an allele is a segment of a dna molecule that controls replication of a gene.

Select the correct answer from each drop-down menu proteins are

How does the diagram explain ocean currents? earth tilt 23.5 degreesquestion 1 options: earth's tilt causes uneven heating of earth which causes currents.earth's tilt causes the ocean to move because of gravity.earth's tilt and its rotation cause currents.earth's tilt causes uneven distribution of salt which causes currents.