3. A stone is thrown upward from the top of a building at an angle of 300 to the horizontal and with an initial speed of 20.0 m/s. The point of release is 45.0 m above the ground, a. How long does it take for the stone to hit the ground? b. What is the stone’s speed at impact?
c. Determine the horizontal range of the stone​

Total solidification times of three casting geometries are to be compared: a sphere, a cylinder, in which the length-to-diameter ration - 1.0, and a cube. volume = 1000 cm^3 for all three shhapes, and the same casting alloy is used. a) determine the solidification times of each geometry b) based on the results of part (a), which geometric element would make the best riser? c) if the mold constant = 3.5 min/cm^2 in chvorinov's rule, compute the total solidification time for each casting.

Matter is needed to transfer thermal energy bya. conductionb. convectionc. radiation d. both a & b.

The electric potential a distance r from a small charge is proportional to what power of the distance from the charge? a. r^-1 b. r c. r^-2 d. r^2