The electronics you use every day would not be possible without metalloids. Which statements are true about metalloids? Choose the three statements that apply. A. They are somewhat reactive.
B. They are soft, solid, and malleable
C. They can be used to make a semiconductor.
D. They have some properties of metals and some of non-metals.​

the answer is barium and copper bromide

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.