Answer:

Gross Yielding:

φTn= 0.90*36 ksi * 10-in. * 0.75-in. = 243 kip

Net fracture:

There are three possible failure modes for the net section:

For failure mode 1, the net section is:

A_n = (10-in. - 2*(13/16-in.))*0.75-in = 6.28 in²

For failure mode 2 and 3, the net section is:

A_n = (10-in. - 3*(13/16-in.)+2*((4-in)²/(4*4-in.))*0.75-in = 9.5625 in²

The smallest area will govern, so failure mode 1 will be the lowest:

φTn = 0.75*58 ksi * 6.28in2 = 273 kip

Thus, the gross section is lower, the answer is 243 kips.