Find a vector function, r(t), that represents the curve of intersection of the two surfaces. The cylinder x2 + y2 = 81 and the surface z = xy.

Mark the brainliest 19 points for you a student uses a liquid thermometer to measure the temperature of a substance in a beaker during science class. the teacher says that the measurement is incorrect. which are the most likely reasons the liquid thermometer could have measured the wrong temperature? check all that apply. the thermometer was not calibrated electronically. the software connected to the thermometer had errors. the bulb of the thermometer was touching the beaker. the thermometer's bulb was not submerged in the substance. the student stirred the substance with the thermometer.