Our rotameter has been calibrated for nitrogen at room temperature and atmospheric pressure; the calibration shows that for a reading (float-position) of 50% of the height of the rotameter tube the volumetric flow rate is 100 cm3/min. we now need to measure the flow of helium at room temperature and atmospheric pressure, using the same rotameter. when the reading is 50% of full scale, estimate the helium volumetric flow rate. for this problem you can consider that the density of float () is much higher than that of the fluid ( ).