Please help I Need The Right Answer!! A group of scientists studied the environmental impact of internal combustion engines burning hydrocarbon fuels. The scientists equipped four vehicles with devices to capture and measure particulate emissions. One vehicle burned diesel fuel, one burned ordinary gasoline, one burned a gasoline/ethanol mixture, and one burned natural gas. The four vehicles had equal masses and carried identical cargo. The scientists drove each vehicle 400 kilometers, recording the volume of fuel burned and the quantity of particulate emissions generated. What is the independent variable in this experiment?

A.
type of fuel

B.
distance traveled

C.
mass of vehicle and cargo

D.
quantity of particulate emissions

A. type of fuel

Explanation:

The scientists combusted different types of hydrocarbons (different type of fuel)

1: most common garden plants prefer loam — soils with a balance of different-sized mineral particles (approximately 40% sand, 40% silt, and 20% clay) with ample organic matter and pore space. however, some plants grow better in sandy soils, while others are well-adapted to clay soils.

2: available water capacity is the maximum amount of plant available water a soil can provide. it is an indicator of a soil's ability to retain water and make it sufficiently available for plant use. available water capacity is the water held in soil between its field capacity and permanent wilting point.

3: it is the same for all living things (plants and animals). it also includes very tiny organisms that our eyes cannot see. they are known as microorganisms, and include viruses, bacteria and fungi.

im not intirely sure but i think the anwser is d relative humidity