$10.)$ a$)$ What is thermal bridging?

b$)$ If a manufacturer is fabricating a metal window, how would they reduce the issue of

thermal bridging?

c$)$ What is a better window for dealing with thermal bridging: a wood window or a

metal window?

$11.)$ A roof covers a building area of $40-$feet in width by $80-$feet in length. The roof is heavily

insulated with R$-38$ insulation. The design temperature is $-5$ F and it is desired to maintain a

$70$ F indoor temperature. What is the heat loss through the roof in BTUh?