Answer:
0.0321 g
Explanation:
Let helium specific heat 
Assuming no energy is lost in the process, by the law of energy conservation we can state that the 20J work done is from the heat transfer to heat it up from 273K to 393K, which is a difference of ΔT = 393 - 273 = 120 K. We have the following heat transfer equation:

where
is the mass of helium, which we are looking for:

Answer:
False statement = There must be a non-zero net force acting on the object.
Explanation:
An object is moving at a constant speed along a straight line. If the speed is constant then its velocity must be constant. We know that the rate of change of velocity is called acceleration of the object i.e.

a = 0
⇒ The acceleration of the object is zero.
The product of force and acceleration gives the magnitude of force acting on the object i.e.
F = m a = 0
⇒ The net force acting on the object must be zero.
So, the option (a) is not true. This is because the force acting on the object is zero. First option contradicts the fact.
There would be martial law (just elaborate on the definition) and the population would go awry(elaborate on subject)
Answer:
D. Meters/Seconds
Explanation:
The time period of a wave is measured in seconds.
A typical wave involves both time and distance. Consider a sound wave, which is basically a periodic modulation of the local air pressure. We "hear" the sound because our ears respond to the variations of pressure.
The most common metric of a sound wave is frequency. This is the rate at which the change in pressure occurs, and is measured in cycles per second, formally known as "hertz". The period is the inverse of frequency andl has the units of seconds per cycle, commonly stated simply as seconds.
<span>5. Dry ice is an example of _________, which is the process of a solid turning directly into a gas. (1 point)
sublimation
6. The ____ is a unit of force. (1 point)
</span>n<span>ewton
7. Which of the following is the boiling point of water? (1 point)
100°C
8. Which of the following describes the molecular structure of water at 40°C? (1 point)
water molecules are close together and moving freely around each other </span>