The LCM of 24 and 30 is 120.
The minimum cost for 20 crates would be 68 dollars. You would buy 18 crates using the 3 for 10 dollars ( this would cost 60 dollars), and then 2 crates using the one crate for 4 dollars (this would cost 8 dollars) all together you would have 20 crates, costing you 68 dollars.
Answer:

Step-by-step explanation:
To calculate the angles of the given triangle, we can use the law of cosines:

Then, given the sides a=2, b=9, and c=8.

For B:

Answer:
The correct answer with step-by-step explanation: