Which of these describe the composition of earths atmosphere?

A) mixture

B) substance

C) compound

How are joules measured?

Your electricity bill says 834-kWh of consumption. With this amount of energy, how many 59-W light bulbs can be powered for an average of 7 hours?

By looking closely at how stars and galaxies are moving away from other, what have astronomers been able to calculate A. The age of the universe only B. The rate at Which the universe is expanding only C.

What does it mean to say that current and voltage in a circuit are directly related?

A 20 kilogram ball rolls down a 10 meter ramp at the rate of 15 meters per second. The kinetic energy is joules

If the graph represents speed what is measured on the x and y axes

It is difficult to lift a heavy stone than the lighter one on the earth, why?

The vapor pressure of ethanol at 25 degrees C is 7.83 kPa. Calculate the vapor pressure in atm. Round answer to 3 significant digits.

According to Newton's second law of motion acceleration or an object depends upon the ___ of the object and the ___ Acting on it. I'm confused on what the blanks are. I can't find them.

What is the concentration of H + ions at a pH = 7?