Even though water evaporates from the surface, the earth has water and is not dried out. what step to bring water back to earth. which one is correct explain how and why

(a) condensation
(b) precipitation
(c) freezing
(d) melting

i will mark you brainliest .

What happened in 2012 and how does it illustrate the importance of understanding the sun and how it works?

What is the wavelength of a 3*10^12 hz infrared wave a 3*10^20m b 1* 10^4m c 3*10^-3m d 1*10^-4 m

Consider the following unbalanced equation for the combustion of hexane: αc6h14(g)+βo2(g)→γco2(g)+δh2o(g) part a balance the equation. give your answer as an ordered set of numbers α, β, γ, use the least possible integers for the coefficients. α α , β, γ, δ = nothing request answer part b determine how many moles of o2 are required to react completely with 5.6 moles c6h14. express your answer using two significant figures. n n = nothing mol request answer provide feedback