a rope of which a calf is tied is increased from 12 m to 25 m , how much additional grassy ground shall it graze ?
"π ( 252 – 122 ) = 1511.71 answer : d"
multiply(subtract(power(25, const_2), power(const_10, const_2)), divide(add(multiply(12, const_2), const_2), add(const_4, const_3)))