A, b,c, or d please help

What causes most sediment to wash or fall into a river

What is the wavelength of a wave with a velocity of 50 m/s and a frequency of 5hz a 250 m b 0.1 m c 10m d 0.01 m

Which order shows the levels of organization from largest to smallest? organism, organ system, cell, organ, tissue organism, tissue, organ system, organ, cell organism, organ, organ system, cell, tissue organism, organ system, organ, tissue, cell