Learners mentally manipulate two-dimensional diagrams to visualize the objects in their three-dimensional forms.

In this learning activity, you'll discuss shifting perceptions of parents at different life stages.

Students read how to determine and calculate the saturated unit weight for a given sample of soil or aggregate, based on the weight-volume relationship. Practice problems complete the activity.

Students read how to determine and calculate the degree of saturation for a given sample of soil or aggregate based on the weight-volume relationship.

In this animated object, learners examine the relationship between pressure and temperature in an air conditioning system.

Students read an explanation of the use of weight-volume relationships and practice calculating density.

Learners view a demonstration showing that line-neutral voltages and line-line voltages are not in-phase with each other, but have a definite 30-degree relationship.

Students read how to determine and calculate the porosity for a given sample of soil or aggregate, based on the weight-volume relationship.

In this animated activity, students read about weight-volume relationships within a given sample of soil or aggregate. They complete problems using a 3-phase diagram.

Learners will examine the four steps to listen actively to improve relationships.

Students read how to determine and calculate the void ratio for a given sample of soil or aggregate based on the weight-volume relationship.

Students read how to determine and calculate the saturated density for a given sample of soil or aggregate, based on the mass-volume relationship. Practice problems complete the activity.

Students read how to determine and calculate the dry unit weight for a given sample of soil or aggregate based on the weight-volume relationship.

Students read how to determine and calculate the dry density for a given sample of soil or aggregate based on the mass-volume relationship.

Learners examine three formulas than can be used to find dc power. Examples are given.

In this learning activity you'll examine how firewalls block viruses by discussing trusted, semi-trusted, and untrusted networks.

This interactive learning object demonstrates how the moisture content is determined for a given sample of soil or aggregate.

Students read about the concept of unit weight relating to the 3-phase diagram and perform calculations.

In this learning activity you'll explain how voltage and resistance in a series circuit affect current flow.

In this interactive object, learners vary the value of the resistance to see how it affects current. Example problems are included.