Can someone help me with this

4π

Step-by-step explanation:

This is a sinusoidal function.

The period of the function is basically the length from one wave crest to the next crest. We can take any 2 subsequent crests.

Lets take our first crest to be at 3π

The next one will be at 7π, as we can see

So, the length from one crest to the next is the period, which is:

7π - 3π

= 4π

Third answer choice is right, 4π is the period.

step-by-step explanation:

i have done this all on a piece of paper but idk how to put it on here cuz it needs to be drawn

7.9m and 4.3°

step-by-step explanation:

let east be +x and north be +y, x = distance * cos θ, y = distance * sin θ  

for 3.5 south, y = -3.5  

for 8.2, x = 8.2 * cos 30 and y = 8.2 * sin 30  

for 15 west, x = -15  

total x = 8.2 * cos 30 – 15 ≈ -7.9  

total y = -3.5 + 8.2 * sin 30 = 0.6  

magnitude = [(8.2 * cos 30 – 15)^2 + 0.6^2)]^0.5  

the magnitude is approximately 7.9 m  

tan θ = y/x = 0.6/-7.9  

the angle is approximately 4.3˚ north of west