Can someone help me with this ASAP please?

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.

Do you think defendants should have be found guilty beyond a reasonable doubt to be convicted? or do you think a lesser burden of proof, like the preponderance of evidence in needed in civil cases, is more appropriate?

This table shows data collected by a weather station. if these trends continue, what weather can you predict for the region for the upcoming week? day 1 day 2 day 3 temperature, upper atmosphere (ºf) 45 44 43 temperature, surface (ºf) 61 59 55 air pressure (inches of mercury) 30.00 29.96 29.50 a. fair skies, warm weather b. a blizzard c. rain storms d. a few clouds, but very cold