Chert has the following properties:
• made up of very fine sediment
grains
no fixed crystal structure
found in nature
solid
not a pure substance
• not made by organisms

Is chert a mineral or a rock?

Chert is a rock.

Rocks don't have any fixed crystal structures and, as many people know, not a pure substance

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.

im doing test rn im going with 2 but ill give answer if itss wrong,   : )