How do you determine the standard error on the slope in a simple harmonic motion graph​

When you push downward on a book at rest on a table, you feel an upward force. does this force depend on friction? defend your answer.

What is the relationship between the direction of motion of the balloon and the wind currents

What conclusion can be made based on the temperature of soil when the light hits the soil at 0°, 45°, and 90° angles in section 2 of the experiment? did your results support your hypothesis? why or why not?