Need help it’s about “waves in the world around you “

Which scientific design has both practical limitations and limitations due to scale? studying the effect of bleach on the growth of mold spores exposing cultures of duckweed to different intensities of light observing the replication of dna molecules with a hand lens using colored marbles to model a cross between two colors of rabbits

As water is cooled from 4 to 0, its density

What is a quantitative observation? a. an observation that proves the hypothesis is wrong. b. an observation about the number or amount of something. c. an observation about the color, shape, size, or condition of something. d. an observation in which the appearance of something is described using descriptive language.