Two scientists wanted to determine if soil type affects the growth of plants. They each prepared an experiment. Scientist 1:
Take four plants and pot them in styrofoam coffee cups. Give them each the same amount of soil. Use potting soil for the first seed, sand for the second seed, gravel for the third seed, and mulch for the fourth seed. Put two of the cups in the window and two in the basement. See which plant grows better.

Scientist 2:
Take four bean seeds. Plant each seed in a 3 inch clay pot. Plant each one with 5 cm deep of soil. Place the seed 2 cm beneath the surface of the soil. Use potting soil for the first seed, sand for the
second seed, gravel for the third seed, and mulch for the fourth seed. Put all pots in a room where the temperature is controlled at 68 degrees Fahrenheit. Give all of the plants 12 hours of light per
day with a 40 watt light bulb, 30 cm above the pots. Water each plant with 20 mL of tap water at noon each day. If and when each seed germinates, measure the height of each plant with a metric ruler every two days. Record data for two weeks.

Which scientist prepared a better experiment? Why?

What, if anything, is wrong with the first scientist’s experiment?

What, if anything, is wrong with the second scientist’s experiment?