Answer:
<h2>A) 3 cm</h2>
Step-by-step explanation:
The formula of a volume of a cylinder:

r - radius
H - height
We have r = 1cm and H = 21cm. Substitute:

The formula of a cone:

r - radius
H - height
We have V = 21π cm³ and H = 7cm. Substitute:
<em>divide both sides by π</em>
<em>divide both sides by 7</em>
<em>multiply both sides by 3</em>

Answer: PiN, Pi/3+2PiN, 5Pi/3+2PiN
Step-by-step explanation: Use formula sheet
Answer:
Pete: 39, Linda: 42
Step-by-step explanation:
Suppose Pete has x dollars. If he has 3 dollars less than Linda, then Linda has 3+x dollars. Together, they have 81 dollars:
x+3+x=81
2x+3=81
2x=78
x=39
Since Pete has x dollars, and x=39, he has $39.
Linda has 3+x, which is 39+3 = $42
<em>I hope this helps! :)</em>