Pumping tests consist of pumping at 100 percent capacity at 150 psi, 70 percent at 200 psi and __________ percent at __________ psi.

Pumping tests are critical for evaluating a fire apparatus's performance under various conditions. The specified parameters in the question are intended to assess the pump's efficiency at different percentages of its capacity and corresponding pressure levels.

The correct answer indicates that at 50 percent capacity, the pump should operate at 250 psi. This reflects a common test condition that allows the operator to understand how the pump performs under moderate load while avoiding strain on the pump and the apparatus.

Understanding these specific test percentages and pressures is essential for fire apparatus operators, as it helps them determine how their equipment will perform in actual firefighting scenarios. The ranges provided in the question represent a typical progression through pressure tests, allowing for a comprehensive evaluation across multiple operational levels.

The other parameters do not align with standard practices for testing pump capacities efficiently or may represent pressure levels that are either too high or low for the specific percentages of flow being measured.