A long footing. $3 \mathrm{ft}$ wide, is located in the slope of a hill whose inclination is $30^{\circ}$. The sevil of the hill is sand that has an angle of internal friction of $35^{\circ}$ and a unit weight of 115 pef. If a $D / B$ ratio of 1 is assumed, what wall looding can the footing carry? Use a factor of safety of 3