-3 2/3 I just changed the mixed number into a improper fraction
Answer:

Step-by-step explanation:
This half life exponential decay equation goes by the formula:

Where

Since half life is given as 22, we plug that into "Half-Life" in the formula for k and then plug in the formula for k into the exponential decay formula:
So,

Now

third choice is correct.
180=11+2x
-11 -11
169/2=2x\2
x=84.5
The given info is sufficient to warrant the conclusion that both triangles are 45-45-90 triangles.
The measure of angle B is 45 degrees, or pi/4 radians.
The cosine of this angle B is 1/√2, or √(2)/2. This is approx. 0.707.