Mary believes that cognitive development is a matter of gradual and almost imperceptible changes over time. her viewpoint is most directly relevant to the issue of?

In which research method does a researcher change the value of one variable to determine how the change affects another variable? a. experiment b. observational research c. survey d. case study

Can i have all the nicknames of all 50 states of usa?

Thermal expansion is an example of? a) mechanical weathering b) chemical weathering c) erosion d) molecular weathering