Which climate zone has hot summers, cold winters, and average amounts of precipitation throughout the year? A. Equator
B. Polar
C. Temperate
D. Tropical

What happens when the number of protons in an atom changes

Aspring has a relaxed length of 33 cm (0.33 m) and its spring stiffness is 6 n/m. you glue a 76 gram block (0.076 kg) to the top of the spring, and push the block down, compressing the spring so its total length is 15 cm. you make sure the block is at rest, then at time t=0 you quickly move your hand away. the block begins to move upward, because the upward force on the block by the spring is greater than the downward force on the block by the earth. calculate y vs. time for the block during a 0.09-second interval after you release the block, by applying the momentum principle in three steps each of 0.03-second duration.

Aball is fired with an initial velocity of 500 m/s at an angle of 30 degrees above the horizontal across a level field. a. what are the horizontal and vertical components of the initial velocity. b. calculate the maximum height, the time of flight, and the range of the ball.