PLEASE HELP!!! A person stands 6.00m from a speaker and 8.00m from an identical speaker. What is the frequency of the second (n=2) interference minimum (destructive)? (unit= Hz)

Moon effect. some people believe that the moon controls their activities. if the moon moves from being directly on the opposite side of earth from you to being directly overhead, by what percentage does (a) the moon's gravitational pull on you increase and (b) your weight (as measured on a scale) decrease? assume that the earth–moon (center-to-center) distance is 3.82 × 10^8 m, earth's radius is 6.37 × 10^6 m, moon's mass is 7.36 × 10^22 kg, and earth's mass is 5.98 × 10^24 kg.

What tightening torque should be used for a hexagonal head screw (not split-bolt) on a 250 kcmil conductor?

You are given a vector a = 125i and an unknown vector b that is perpendicular to a. the cross-product of these two vectors is a × b = 98k. what is the y-component of vector b?