1. 5. what is the frequency of a wave that has a wave speed of 120 m/s and a wavelength of 0.40 m

300 Hz

Step-by-step explanation:

Something may be wrong on my end because I only see a question labeled 5. Anyways, you can basically just follow the units here.

So in order to use the given info to get the correct units...

Plugging in or knowns gives us:

Frequency = (120/.4) = 300 Hz

This might be an informal way to think about it technically but it's a good way to do it nonetheless.

b

step-by-step explanation:

the equation of a line in point- slope form is

y - b = m(x - a)

where m is the slope and (a, b) a point on the line

calculate m using the slope formula

m = (y₂ - y₁ ) / (x₂ - x₁ )

with (x₁, y₁ ) = (0, 4) and (x₂, y₂ ) = (3, - 5) ← 2 points on the line

m = = = - 3

with m = - 3 and (a, b) = (3, - 5), then

y - (- 5) = - 3(x - 3), that is

y + 5 = - 3(x - 3) → b