here' s what i got for the second problem

Objective function:

1.50 x11+1.50 x21 +1.50x31+1.50x41+2.10x12+2.10x22+2.10x32+2.10x42+2 .85x13+2.85x23 +2.85x33+2.85x43 + 3.4x14+3.4x24+3.4x34+3.4x44

Constraints:

X11=5000

X12=5000+3500

X13= 5000+3500

X14= 5000+3500+4000

X21=3500

X22=3500+6500

X23=3500+6500+4000

X24=0

X31=6500

X32=6500+4000

X33=0

X34=0

X41=4000

X42=0

X43=0

X44=0

X24, x33, x34, x42, x43, x44 = 0