The given triangle is a right angle triangle. The diagram is shown below.
From the triangle, considering angle I as the reference angle,
hypotenuse = JI = 53
adjacent side = IK = 45
opposite side = KJ = 28
To find Sin I, we would apply the Sine trigonometric ratio which is expressed as
Sin # = opposite side/hypotenuse
Thus,
Sin I = 28/53