ANS:E - all the above.

Bernoulli's equation is a fundamental principle in fluid dynamics that relates the pressure, velocity, and elevation of points in a flowing fluid. It is derived from the conservation of energy principle along a streamline in a flow field. The assumptions underlying Bernoulli's equation are as follows:

1. Fluid is non-viscous: Bernoulli's equation assumes that the fluid through which the flow occurs has no viscosity, meaning there is no internal friction between fluid layers as they move past each other.
2. Fluid is homogeneous: Bernoulli's equation assumes that the fluid is homogeneous, meaning it has constant density throughout the flow. This assumption allows for the simplification of the equation by assuming that the fluid properties do not vary significantly over the length scales of interest.
3. Flow is steady: Bernoulli's equation assumes that the flow is steady, meaning the velocity, pressure, and other flow parameters do not change with time at any given point in the flow field.
4. Flow is along the streamline: Bernoulli's equation applies along a streamline, which is a path in the flow field that is tangent to the velocity vector at every point. Along a streamline, the Bernoulli equation can be applied to relate the pressure, velocity, and elevation at different points.