Which gas became part of Earths atmosphere mainly as a result of the evolution of life forms?

Hans stands that the rim of the Grand Canyon and yodels down to the bottom. He hears his echo back from the Canyon floor 5.20 seconds later. Assume that the speed of sound in air is 340.0 m/s. How deep is the canyon at this location?

Infrared radiation has wavelengths ranging from about 800 nm to 1 mm. what is the frequency of radiation of wavelength 960 nm? answer in units of s-1.

If an eagle and a bumblebee are traveling at 8km/hr, which has more momentum? explain.

A train is traveling at an average speed of 80 km/h. which additional quantity would you need to know to calculate the distance the train has traveled based on its average speed? a. velocity b. position c. acceleration d. time traveled

Create a sketch that shows the particles of matter in two substances that differ in density. Label the sketch to show which substance has greater density.

Which equations are balanced? Check all that apply. Mg3N2 + H2O → 3MgO + 2NH3 C3H8 + 5O2 → 4H2O + 3CO2 Zn + 2HCl → ZnCl2 + H2 3Ca (OH) 2 + 2H3PO4 → Ca3 (PO4) 2 + 6H2O 3H2SO4 + 2Fe → Fe2 (SO4) 3 + H2 4Al + 3O2 → 2Al2O3

Covert the names below into formulas in an equation then balance the equation 1.) Aluminum bromide plus chlorine yields aluminum chlorine plus bromine 2.) sodium phosphate + calcium chloride yields calcium phosphate + sodium chloride

In a inverse relationship, when one variable increases, the other

A chair of weight 75.0 N lies atop a horizontal floor; the floor is not frictionless. You push on the chair with a force of F = 42.0 N directed at an angle of 38.0 ∘ below the horizontal and the chair slides along the floor.

A car travels 20 km west, then 20 km south. what is the magnitude of its displacement? A) 0 km B) 20 km C) 28 km D) 40 km