Can i ask for an assistance for these questions? Thanks!

13 What is the equation of the tangent line to the curve (given below) at x=4? * 8 (x) = 3 O y = 2x + 10 Oy = -2x +6 Oy = -2r + 10 14 The function f(x) is not differentiable at what value of "a"? [ f (x) = 1+5 x3 +2:+1 Ou=1 Oa=0 Oa=-1 Oa = 2 15 Which of the following functions is NOT differentiable? * Of ( x) = 1x Of ( x ) = ( x + 3 ) + Of ( x ) = mx +b Of (x) = 2022