Which policy has been a cost-effective way to reduce sulfur dioxide emissions? a) enacting cap-and-trade legislation b) implementing scrubber technology on all power plants c) burning high-sulfur coal d) banning the emissions of sulfur dioxide entirely

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