QUESTION $1(20$ marks$)$

For the pin$-$jointed truss shown in Figure $1$

a$)$ Calculate the support reactions

b$)$ Find the member forces using the Method of joints and show clearly whether the

members are in tension or compression

c$)$ Check the member forces in $BD$ and $BF$ using the Method of sections

d$)$ Determine the minimum cross$-$sectional area for the truss members if the

maximum stresses are $90$MPa for members in tension and $65$MPa for members

in compression