Cars entering our field of vision from the side require the use of ?

You find a mysterious, dull substance on the ground and pick it up for a closer look. it is powdery, very light, and soft to the touch. the substance is most likely i. an organic mineral ii. a metallic mineral iii. a nonmetallic mineral i only ii only iii only i and ii i and iii

Which of these is a disadvantage of hydrogen fuel cells? a. engines that use hydrogen fuel are more efficient than gasoline-powered engines. b. the only emission produced by hydrogen fuel cells is water. c. hydrogen fuel is continually available and useful for heating. d. hydrogen fuel is often purified in a process that emits lots of greenhouse gases.

What property does soil or rock need to be permeable? a.)young b.)old c.)non porous d.)porosity