Find the area of a triangle with sides 21 cm, 28 cm, and 31 cm.

PLZZZ HELP ASAP!

the answer is y = 11.54

hope this : )

where's the diagram?

step-by-step explanation:

the answer is:

the correct option is the option b.

to calculate the surface area of the right cylinder, we need to use the following formula:

from the picture we know that:

so, substituting and calculting we have:

hence, we have that the correct option is the option b.

have a nice day!