Which best describes the path of solar radiation?

1 from the surface of the earth to the sun, where it is absorbed
2 from the sun to the surface of the earth, where it is absorbed or reflected
3 from the surface of the earth to the sun, where it is absorbed or reflected
4 from the sun to the surface of the earth, where it is reflected

Which of the following is an advantage of using embryonic stem cells in medical research? a. the use of embryonic stem cells is much less expensive than the use of adult stem cells. o b. no living tissue is damaged when scientists use embryonic stem cells. o c. embryonic stem cells are able to differentiate into a wider range of cells than adult stem cells. d. there is no controversy surrounding the use of embryonic stem cells.