Which of the following is a disadvantage of using solar energy? a. it requires a high initial investment. b. it is abundantly available. c. it reduces greenhouse gas emissions. d. it is a renewable resource.

Which statement about the immune system is false? a. lymphocytes reduce inflammation, b. b cells remember specific pathogens. c. most white blood cells kill bacteria d. white blood cells are made in lymph nodes.

Human genes only differ by less than percent. a. 1 b. 6 c. 11 d. 16

If the dimensions of a cube-shaped cell with a length,height, and width of 1 micrometer were to double, what would be the cell's new ratio of surface area to volume? a.3 to 1 b.4 to 3 c.1 to 2 d1 to 6