Hi need help on this question

The two slender rods AB and AC of Figure 7.3 are pinned at A and also attached with pins at the blocks B and C, of weight 18 lb and 80 lb respectively. If a load P is applied as shown, with P = 300 lb, determine the minimum coefficient of static friction (at both B and C) for which equilibrium is possible. Neglect the size of the blocks and the weights of the rods. 60 in. 30 in.- AV 25 in. 18 lb B 15 in. 80 1b C Figure 7.3