Why does a helium balloon float in air?

A. Helium is denser than air.

B. Helium is less dense than air.

C. The helium is under pressure in the balloon.

The vertical height of an ocean wave from a crest to a trough is 10 meters. What is the amplitude of the ocean wave?

What do two troughs make when they meet

what is the force of static friction on Earth between a 2000 kg car and the road if a coefficient of static friction is 0.4?

Two types of positions are

A platinum sphere with radius 0.0199 m is totally immersed in mercury. Find the weight of the sphere, the buoyant force acting on the sphere, and the sphere's apparent weight. The densities of platinum and mercury are 2.14*104 kg/m3 and 1.

Oxygen makes up the largest part of living cells at 65%. What is the percentage of the second-most abundant element in living cells?

Acceleration is defined as the rate of change for which of the following? A. time B. velocity C. position D. displacement

What are 3 characteristics of a tornado?

Which list shows the element symbols of the 6 biological elements?

A space probe produces a radio signal pulse. If the pulse reaches Earth 12.3 seconds after it is emitted by the probe, what is the distance from the probe to Earth?