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.

answer:  

step-by-step explanation:

here x represents the height of the pole,

and, the height of the shadow of the pole is 12 feet.

also, the angle of elevation from the top of the pole is 40°,

therefore,

by the low of sine,

which is the required equation for finding the value of x,