Scientific investigation

Which of the following is NOT an example of observation?

• Water evaporates.

• Ice floats on water.

• Leaves are green.

• Rice can provide organisms with energy.

A farmer suspects that the decrease of vegetable production is due to a new fertilizer used. He wants to perform experiments to test if his hypothesis is correct. Which of the following should be the independent variable?

• Amount of fertilizer used

• Brand of fertilizer used

• Amount of vegetable produced

• Kind of vegetables planted

Which of the following can be hypotheses for an investigation?

• Sugar dissolves faster than corn flour.

• Solubility of salt increases with temperature.

• Does the volume of water affect the time taken for the substance to dissolve?

• Sugar is a better solute than corn flour.

If we carry out a fair test in a correct way, the result should always match with the hypothesis.

• True

• False

In a fair test, all variables should be kept the same, except the _____ variable.