When a flask when full of air has a mass of 30.98 g. when the air is pumped out the flask has a mass of 30.72 g. find the mass of air in the flask before connecting to the vacuum pump

What sort of waves exhibit the doppler effect?

The illuminance of a surface varies inversely with the square of its distance from the light source. if the illuminance of a surface is 120 lumens per square meter when its distance from a certain light source is 6 meters, by how many meters should the distance of the surface from the source be increased to reduce its illuminance to 30 lumens per square meter?

Answer asap 50 points which of the following illustrates how a venus fly trap senses that an insect has landed in its open leaves? 1. using tiny hairs, the leaves sense a change in light. 2. using tiny hairs, the leaves taste a chemical. 3. using tiny hairs, the leaves detect a touch. 4. using tiny hairs, the leaves sense a change in water levels.