Why does a balloon filled with hydrogen rises up only to a certain height

what is a statement that describes what scientists expect to happen everytime under a particular set of conditions.

Which are uses of convex mirrors? Check all that apply. -magnifying mirrors for putting on makeup -side-view mirrors on vehicles -hallway safety mirrors -focusing automobile headlights -lenses in sunglasses

What occurred during the Cenozoic era? A. a meteor impact B. the ice age C. dinosaur extinction D. plants and animals first colonize on land

If two observers in the Northern Hemisphere are 500 miles apart but are at the same latitude, which of these statements will be true? A. Polaris will be seen by both observers at the same azimuth. B.

How to find concentration from absorbance?

An impala is an African antelope capable of a remarkable vertical leap. In one recorded leap, a 45 kg impala went into a deep crouch, pushed straight up for 0.21 s, and reached a height of 2.5 m above the ground.

The metric unit of force is the Newton (N), which is kg∙m/s^2. Convert 10 mg∙cm/s^2 to Newtons. Be careful when working with units. A. 1 x 10^-2 N B. 1 x 10^-5 N C. 1 x 10^-6 N D. 1 x 10^-7 N

Which of the following aspects of the environmental movement addresses the public's right to intervene in environmentally damaging activities on private land?

A mine elevator is supported by a single steel cable 0.0125 m in diameter. The total mass of the elevator cage and occupants is 6450 kg. By how much does the cable stretch when the elevator hangs by 362 m of cable? (Neglect the mass of the cable.

What scientific practice is this? 1) collecting data 2) asking a question 3) providing explanations 4) communicating results