You climb to the top of a ladder. You drop a a ball from height H, it reaches the ground with speed V if there is no air resistance. From what height should you drop it so it will reach the ground with three times the original speed? √3H
H
6H
9H

(pls help its due today)

An object weighs 40n in air, weighs 20n when submerged in water and 30n when submerged in a liquid of unknown density. what is the density of the liquid?

At an oceanside nuclear power plant, seawater is used as part of the cooling system. this raises the temperature of the water that is discharged back into the ocean. the amount that the water temperature is raised has a uniform distribution over the interval from 10° to 25° c. what is the standard deviation of the temperature increase?

Which branches of natural science include the study of an organism that lived 10 million years ago