Can Somebody help me real fast?

4. a spring scale is constructed so that each 0.10-n increment is separated by 0.50 cm. what spring constant is necessary for the scale to be accurate? -1.0n/cm -0.10n/cm -9.8 n/cm -0.20n/cm

Aball is thrown from a height of 139 feet with an initial downward velocity of 15 ft/s. the ball's height h (in feet) after t seconds is given by the following. h=139-15t-16t^2 how long after the ball is thrown does it hit the ground? round your answer(s) to the nearest hundredth. (if there is more than one answer, use the "or" button.) t =

Me with geometry ! in this figure, bc is a perpendicular bisects of kj. dm is the angle bisects of bdj. what is the measure of bdm? •60° •90° •30° •45°