The most reasonable would be grams.
B. 12
Ex: 12 squared is 144
The solution of cos θ = −0.3 is θ = 107.45760312 degrees
<em><u>Solution:</u></em>
Given that we have to find the primary solution of 
To solve this equation, you must find the unknown (theta)

Use the inverse of cosine (Arccos) to find the angle measurement (in degrees) of theta

We know that arccos (-0.3) = 107.45760312 degrees
[ If you reference a unit circle or use a calculator ]

Therefore solution of cos θ = −0.3 is θ = 107.45760312 degrees
Answer:
Step-by-step explanation:
From the picture attached,
∠4 = 45°, ∠5 = 135° and ∠10 = ∠11
Part A
∠1 = ∠4 = 45° [Vertically opposite angles]
∠1 + ∠3 = 180° [Linear pair of angles]
∠3 = 180° - ∠1
= 180° - 45°
= 135°
∠2 = ∠3 = 135° [Vertically opposite angles]
∠8 = ∠5 = 135° [Vertically opposite angles]
∠5 + ∠6 = 180° [Linear pair of angles]
∠6 = 180° - 135°
∠6 = 45°
∠7 = ∠6 = 45° [Vertically opposite angles]
By triangle sum theorem,
m∠4 + m∠7 + m∠10 = 180°
45° + 45° + m∠10 = 180°
m∠10 = 180° - 90°
m∠10 = 90°
m∠10 = m∠12 = 90° [Vertically opposite angles]
m∠10 = m∠11 = 90° [Given]
Part B
1). ∠1 ≅ ∠4 [Vertically opposite angles]
2). ∠7 + ∠5 = 180° [Linear pair]
3). ∠9 + ∠10 = 180° [Linear pair]