Can someone explain this to me please?

Option C

Step-by-step explanation:

Since, measure of all sides of the triangle has been given in the picture,

By applying cosine rule in the given triangle,

AC² = AB² + BC² - 2(AB)(BC)cos(B)

11² = 16² + 16² - 2(16)(16)cos(B)

121 = 256 + 256 - 512.cos(B)

121 - 512 = - 512.cos(B)

cos(B) = = 0.763672

B =

B = 40.2°

Therefore, measure of angle B is 40.2°.

Option C is the answer.

19.

step-by-step explanation:

you add the 9 in the tens column since it is a single digit and 9 plus zero is 9 so it is 19

which expression can be used to convert 80 us dollars (usd) to australian dollars (aud)?

1 usd = 1.0343 aud

1 aud = 0.9668 usd

step-by-step explanation:

sorry just need the points