Which statements describe abiotic factors in an environment? check all that apply.

chickens run around a farm.
soil retains water and nutrients.
several rocks rest in a stream.
plants compete for sunlight in an ecosystem.
clouds create shade that changes temperatures.

3 1/4 %

explanation:

im not exactly sure but i think its b!

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.