Răspuns:
Explicație pas cu pas:
1. R=8cm, ⇒D=2·R=2·8=16cm; Lc=2·π·R=2·ππ·8=16π cm; Ad=π·R²=π·8²=64π cm².
2. D=12cm, ⇒R=D:2=12:2=6cm; Lc=π·D=π·12=12π cm; Ad=π·R²=π·6²=36π cm².
3. Lc=50π cm, ⇒D·π=50π ⇒D=50cm; R=D:2=50:2=25cm; Ad=π·R²=π·25²=625π cm².
4. Ad=100π cm² , ⇒π·R²=100π ⇒R²=100 ⇒R=10cm; D=2·R=2·10=20cm; Lc=D·π=20π cm.
5. D=16cm, ⇒R=D:2=16:2=8cm; Lc=π·D=16π cm; Ad=π·R²=π·8²=64πcm²
