Thousands of years ago, giraffes with short necks were common within giraffe populations. nearly all giraffe populations today have long necks. this difference could be due to

as a general rule, scissors have blades less than 6 in (15 cm) long and usually have handles with finger holes of the same size. shears have blades scissors used to cut hair or fabric must be much sharper.

the independent variable, or the one that is intentionally manipulated is the speed.