Question

Va rog cât mai repede (azi ne controleaza la teme) 2-b, 3-b , 4-b; pe un caiet

Answer 1

2. b) lung= 2πr= 2•7,5π=25π (cm)

3. b) lung= 2πr= 5 => r=5π/2π=2,5

diametru=2r=2•2,5=5 (cm)

4.b)

$aria = \pi {r}^{2} = { ( \frac{9}{2}) }^{2} \pi = \frac{81}{4} \pi( {cm}^{2} )$