MOCAS 100
A student places a piece of chocolate, a piece of sugar-free
butterscotch, and a pebble on the sidewalk and counts how
many ants are attracted to each over ten minutes. The student
does this for five days, and records the information in the following table.
Chocolate
Butterscotch
Pebble
Day 1
Day 2 Day 3 Day 4 Day 5
(Number (Number (Number (Number (Number
of Ants)
of Ants) of Ants)
of Ants) of Ants)
5
10
8
5
6
2
7
3
4
1
3
4
5
3
3
Why is it important that the student includes a pebble in the test?
a) Control groups help determine if results are random.
b) Replication shows that results are reliable.
c) Multiple trials increase the reliability of the results.
d) Repetition ensures consistency of results.

Agroup of students is studying convection currents. they fill two identical balloons with the same amount of helium. one balloon is placed in a freezer and the other in an area with warm air. after 10 minutes, the balloons are released from a height of 1 meter. which of the following do the students most likely observe? a. the balloons both rise. the cold balloon is larger than the warm balloon. b. the balloons rise at the same rate. both balloons are the same size. c. the warm balloon expands and rises. the cold balloon shrinks and sinks. d. the cold balloon expands and rises. the warm balloon shrinks and sinks.

When a scientific theory has been tested and proved by the scientific community, it becomes a law

Electromagnets coils of wire paper clips picked up 10 3 15 6 20 9 25 12 ms. owens' class was studying magnets. ms. owens showed her students how to make an electromagnet using a nail, a d-cell battery, and plastic coated wire. the students wrapped the wire around the nail and then attached the ends to the battery. when they were finished, they tested their magnets by investigating how many paperclips their magnets could pick up. they also tested whether they could increase the strength of their electromagnets by using more coils of wire. they recorded the class average of their results in the data table seen here. ms. owens asked her students to graph their data in a line graph. how should the students label the x-axis on their line graph? a) size of battery b) number of paper clips c) number of coils of wire d) strength of electromagnet