Multiple Integration Q8). Perform the following multiple integral over the shaded area shown to determine the total pressure force (KN) exerted on the triangular shaped dam wall: 37.5 pgy dx dy (p = 1000 kgm" ; g = 9.8ms-2) ( Hint: integrate along the x axis first using the equations of the two diagonal lines as limits for the x; then integrate the resulting integral with respect to y y 37.5 i x =-4/3 y - - x = 4/3Y x = -50 x = 50 X Parametric Equations Q9a). Write the parametric equations for a projectile's position, when launched at an angle of 30-deg to the horizontal with an initial speed vo = 20m/s b). Use these parametric equations to find the distance and time to impact, assuming the ground is flat. (g = 9.8 ms z ) 5 Div-Grad-Curl Q10). Find the Gradient of the scalar field @ (x, y) = 2y2 x + 3y2 Q11). Find the Divergence of these electric fields - which of these could be associated with the presence of electric charges and what are the sign of the charges ? - explain your answer. =). E1 = 3y i - 6yj . b). En= 2zi + 2x j Q12). Find the Curl of the following vector fields: =). B = - 3zj + 4yk; b). E = 2xi + 3yi Which of these fields could be a magnetic field associated with a current source and in which direction is the current flowing ? - explain your