If I raise the Celsius scale by 15 degrees, how
much will I be raising it in the Kelvin Scale?

If the change is +15 degrees Celsius, the change is +15 Kelvin (note that it's not degrees Kelvin, just simply Kelvin). You can use the conversion, which is 273.15 Kelvin = zero degrees Celsius. Since it's a relative scale, 10 C = 274.15 K, and 20 C = 275.15 and so forth.

c. electrical charges of ionic bonds.

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.