Question 1188936
Here's how to calculate the discharge of water flowing into the tank:

**1. Find the radius of the water surface:**

*   We can use similar triangles to relate the radius of the water surface (r) to the depth of the water (h).
*   The ratio of the radii is equal to the ratio of the heights:

    (r - 1) / (1.5 - 1) = h / 4

    r - 1 = 0.5h / 4

    r = 1 + 0.125h

*   When h = 1.2 m:

    r = 1 + 0.125 * 1.2 = 1.15 m

**2. Calculate the cross-sectional area of the water surface:**

*   A = πr²
*   A = π * (1.15)² ≈ 4.1548 m²

**3. Calculate the discharge (dV/dt):**

*   The discharge is the rate of change of volume (dV/dt), which is equal to the cross-sectional area (A) times the rate of change of the water depth (dh/dt).
*   dV/dt = A * dh/dt
*   dV/dt = 4.1548 m² * 0.012 m/s
*   dV/dt ≈ 0.049857 m³/s

**Answer:**

The discharge of water flowing into the tank is approximately 0.049857 m³/s.