Answer:
90
Step-by-step explanation:
why my answer has to be 20 characters long? :)
For this case we have that by definition, the surface area of a cone is given by:

Where:
A: It's the radio
s: It's the slant
Substituting according to the data we have:

If we round:

Answer:
True
-10.
Solution: Multiply the negative three fourths by everything in the parenthesis.

Add the negative three halves to both sides.

Multiply both sides by negative four thirds.

Answer:
210.
Step-by-step explanation:
10.5 x 20 = 210
i hope that helps!!!