Answer :

ko3st

Answer:

B) 9 cm

Step-by-step explanation:

Just look at the triangle and use Pythagoras theoreum.

a² + b² = c²

a = 9 9 - 4.9 = 5

b = ?

c = 10

5² + b² = 10²

b² = 100 - 25

b² = 75

b = + - SQRT( 75 )

{Only the positive term has a meaning here.}

b = 8.66 rounded that is 9, which is answer B.