What is the percent of nitrogen (N) by mass in a 55.0 g sample of Fe(NO3)3? The molar mass of Fe(NO3)3 is 241.86 g/mol. 1. 9.55 g
2. 9.55%
3. 5.80 g
4. 52.2%
5. 17.4 g
6. 5.80%
7. 17.4%
8. 52.2 g

answerlinnaeus;

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.

i believe it is c for plato