3. Carbon dioxide is a gaseous waste that exits the body when you exhale. This demonstrates the respiratory system working with which of the following systems? A muscular B immune C nervous D excretory

Cathy hypothesized that corn would not grow in mud. to test this hypothesis, she took corn kernels and placed 5 in mud, 3 in soil, and 2 in water. to her surprise, the kernels in the mud grew faster than the kernels in the soil. what error might have caused these unexpected results? a. wrong hypothesis b. not enough variables c. undefined control d. too many variables