Answer:
2/21+6/7 = 20/21
Step-by-step explanation:
2/21+6/7
=2/21+(6*3/7*3)
=2/21+18/21
=20/21
Hope this helps! Comment any questions <3
V=pir^2(h/3)
V= 3.14x18^2x6/3
V= about <span>2034.72</span>
Sorry, I know it's a little late.The answer is -6a^2 b^4 c^3