The variable b represents the area of the base of the prism or pyramid. Hope that helps!
The probability would be 1/2
Answer:

Step-by-step explanation:

Move 3k to left hand side and change it's sign
Similarly, move 4.5 to right hand side and change it's sign

Collect like terms

Subtract 4.5 from 18

Divide both sides by 4.5

Calculate

Hope I helped!
Best regards! :D
The answer is D, I'm 95% sure, double check just in case