A horizontal force of at least 150N is required to start moving a 750N crate initialy at rest on a horizontal fioor the coefficient of static friction between the crate and the floor is?

Can someone explain to me how to do this problem ?

15. one purpose of the tread pattern on a tire is to a reduce tire wear. b. reduce traction c. allow water to flow away from the tire. d. look impressive.

Find the dimensions and area of the largest rectangle that can be inscribed in the upper half of the ellipse. (give your answers in terms of a and b. enter the dimensions as a comma-separated list.)