PLEAS N FAS
Which statements describe long-term environmental changes? Check all that apply. They occur in minutes or within hundreds of years. They occur in thousands of years or within billions of years. They affect populations and species more slowly than short-term changes. They have an immediate impact on living things. They can affect the DNA of living things over time.

you need to have a picture of the atom that way we can answer it

answerto predict;

answer: semi-infinite solid initially at a uniform temperature of 400 ◦c is cooled at its surface by convection. the cooling fluid at a constant temperature of 200 ◦c has a convective coefficient (ha) of 250 w/m2.k. the physical properties of the solid: k = 20 w/m.k and α = 4 * 10-5  m2/s. using δx = 0.04 m and δt = 10 s. write the finite difference equations describing the transient heat transfer of the first five δx and the temperature profile after 30 s.