Siska hit a golf ball into the air with an initial velocity of 56 feet per second. the height h in feet of the ball above the ground can be modeled by h=-16t^{2}+56t, where t is the time in seconds after sisika hit the ball. find the time it takes the ball to reach 49 feet above the ground.

(a) calculate the number of electrons in a small, electrically neutral silver pin that has a mass of 10.0 g. silver has 47 electrons per atom, and its molar mass is 107.87 g/mol. (b) imagine adding electrons to the pin until the negative charge has the very large value 1.00 mc. how many electrons are added for every 109 electrons already present

It is really hard for me right know

Aspaceship starting from a resting position accelerates at a constant rate of 9.8 meters per second per second. how far will the spaceship travel if its final speed is 1 percent the speed of light (300,000,000 m/s)? a. 3.1 × 106 m b. 2.94 × 108 m c. 7.8 × 1010 m d. 4.6 × 1013 m