Which if these is an etiquette rule? (american football)

Question 10 options:

A. Debating with the ref over a call

B. Not communicating with your team

C. Post-game handshake

D. Taunting

Meaning of a nonzero y-intercept to a graph of reaction distance versus speed

A helicopter is ascending vertically with a speed of 5.10m/s. At a height of 105m above the Earth, a package is dropped from a window.

Calculate the frequency, in HZ, of a wave in a string traveling 1.25 m/s, with a wavelength of 0.50m

Which part of the earth is considered to be the center

A 1.0-m-diameter vat of liquid is 2.0 m deep. The pressure at the bottom of the vat is 1.3 atm. What is the mass of the liquid in the vat?

Water is a compound. O A. True B. False

How do air quality scientists ensure the air is cleaned? What steps do they take?

Is a mirrors surface opaque or transparent or translucent?

Sound waves can combine to become bigger or smaller true or false

Archimedes supposedly was asked to determine whether a crown made for the king consisted of pure gold (density of gold is 19.3 * 103 kg/m3). According to legend, he solved this problem by weighing the crown first in air and then in water.