The position of an object is given by x = at^3-bt^2+ct, where a = 4.1 m/s^3, b = 2.2 m/s^2, c = 1.7 m/s, and x and t are in Si units. What is the instantaneous acceleration of the object when t = 0.7 s?

1) a child holds two dogs on two separate leads. the dogs are pulling in different directions. one is pulling a force of 20n north and one is pulling 15n eastwards. calculate the resultant force on the child. state the direction. (use the parallelogram of forces) 2) a force of 20n acts horizontally on an object. a second force of 5n acts at 60 degrees to the first one. calculate the resultant force. worth 20 points, need answers asap with method you x