Given that,
ABC is a right angle triangle, C is the right angle.
To find,
cosB = ?
Solution,
The sum of angle of a triangle is equal to 180 degrees. So,
∠A + ∠B + ∠C = 180°
Put ∠C = 90°
∠A + ∠B + 90° = 180°
∠A + ∠B = 90°
Taking cos with each term.
cosA+cosB = cos (90)
cosA+cosB = 0
cosB=-sinA
Hence, cosB = sinA.
 
        
             
        
        
        
Answer:
It would be C. I and II
Step-by-step explanation:
 
        
             
        
        
        
Answer:
71
Step-by-step explanation:
There are 12 inches in a foot:
12 inches x 5 feet = 60
60 + 11 inches = 71 inches total
 
        
                    
             
        
        
        
Answer:
$12.80
Step-by-step explanation:
Sara bought 4 pounds of coffee.
Each pound (lb) costs $3.20
To find the total cost, multiply the cost per pound ($3.20) with the amount of pounds Sara is going to buy (4): 
4 x 3.20 = $12.80
$12.80 would be the total cost before tax. 
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