Someone help me please

What is the value of n in the equation -1/2(2n+4)+6=-9+4(2n+1)

The price for gasoline is represented by the equation y=3.69x, where y represents the total price for x gallons of gasoline. on a graph, the number of gallons is represented on the horizontal axis, and the total price is represented on the vertical axis. determine whether each statement describes the graph of the equation. select true or false for each statement

Use stokes' theorem to evaluate c f · dr where c is oriented counterclockwise as viewed from above. f(x, y, z) = xyi + 5zj + 7yk, c is the curve of intersection of the plane x + z = 8 and the cylinder x2 + y2 = 81.