3. When you skateboard on a ramp,
A sliding friction occurs.
B static friction occurs.
C rolling friction occurs.
D fluid friction occurs.

Which statement best explains why cells were observed in more detail using a compound microscope than a simple microscope? a compound microscope has greater magnification ability than a simple microscope. the compound microscope was invented before the simple microscope. a compound microscope is much easier to manufacture than a simple microscope. compound microscopes were more common than simple microscopes.