Answer:
(a) Tracheids and Vessels
Answer:
The question is incomplete, the questions asked by the students were as follows:
1. What kind of plant life grows naturally in the town park?
2. Which types of treats do different types of dogs like best?
3. Do different types of grass affect how far a ball rolls?
4. How are the chemicals in different vegetables similar?
The answer is 3
Explanation:
Three types of investigation are used by scientists to solve a problem or answer a question. These questions are: comparative investigation, descriptive investigation and experimental investigation. Experimental investigations are conducted to test the relationship between two variables. In the test, one of the variable is manipulated (independent variable) while the other responds (dependent variable).
In this case involving questions asked for a science fair, HOW DIFFERENT TYPES OF GRASS AFFECT BALL ROLLS is most likely an experimental investigation because it is testing the effects of grass type (independent variable) on ball roll (dependent variable).
