For a steady two-dimensional flow, identify the boundary layer approximations. A. The velocity component in the flow direction is much larger than that in the normal direction.
B. The temperature and velocity gradients normal to the flow are much greater than those along the flow direction.
C. The temperature and velocity gradients normal to the flow are much less than those along the flow direction.
D. The velocity component in the flow direction is much less than that in the normal direction.

Explanation:

For a steady two-dimensional flow the boundary layer approximations are The velocity component in the flow direction is much larger than that in the normal direction and The temperature and velocity gradients normal to the flow are much greater than those along the flow direction

assuming Vx ⇒ V∞ ⇒ U and Vy ⇒ u from continuity equation we know that

Vy << Vx

the answer is the first electromagnet (a). this is because it has more coils around the ferromagnetic material. increasing the number of coils increases the surface area in which the metal interacts with the current in the coil. this enables more atoms in the metal to become aligned hence becoming more magnetized.

1) estimating temperature to the nearest tenth of a degree

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4) the position of the cups of sand and water under the heat lamp