1. **Stating the problem:** We have a horizontal beam supported at two points: a left roller support (Rb1) and a right pin support (Rb2). The beam experiences four upward forces. Given values are $Rb1 = 77.25$, $Rb2 = 105.44$, and $W = 10.3$. We need to create the shear force (V) and bending moment (M) diagrams. 2. **Understanding shear force and bending moment:** - The shear force at a section is the algebraic sum of vertical forces to the left or right of the section. - The bending moment at a section is the algebraic sum of moments about that section. 3. **Shear force diagram (V):** - Start from the left end of the beam. - At the left support, the shear force jumps up by $Rb1 = 77.25$. - Moving right, subtract any applied loads (not specified here, so assume only $W=10.3$ acts at some point). - At the right support, the shear force jumps down by $Rb2 = 105.44$. 4. **Bending moment diagram (M):** - The bending moment at the supports (roller and pin) is zero. - Calculate moments at points of load application by integrating the shear force diagram or summing moments. 5. **Formulas:** - Shear force $V(x) = \sum F_y$ to the left of section $x$. - Bending moment $M(x) = \sum (F_y \times \text{distance from } x)$. 6. **Diagram description:** - The shear force diagram will have jumps at the supports corresponding to $Rb1$ and $Rb2$. - The moment diagram will be a curve starting and ending at zero at the supports, with a maximum moment somewhere between. Since exact load positions are not given, the diagrams will show the reactions and general shape. Final answer: Shear force diagram: starts at 0, jumps to 77.25 at left support, remains constant or changes with loads, then drops by 105.44 at right support. Moment diagram: zero at supports, maximum moment between supports depending on load positions.