Một vật dao động điều hòa theo phương trình x=6cos(4πt),vật tốc của vật tại thời điểm t=7,5s

What changes occur in the brain during the teenage years? 25 points, someone me out!a.) thinking becomes slower as the brain grows larger. b.) connections between neurons become stronger and faster. c.) unused neurons fuse together to form larger, better functioning neurons. d.) more neurons are developed.

Arunner is training for an upcoming marathon by running around a 100-m-diameter circular track at constant speed. let a coordinate system have its origin at the center of the circle with the x-axis pointing east and the y-axis north. the runner starts at (x, y) = (50 m, 0 m) and runs 2.5 times around the track in a clockwise direction.

For waves in the ocean, the medium of the waves is a. air b. water c. energy d. a passing boat