If the length of a solenoid is doubled and the current passing through it is increased 9 times, the magnetic field inside the solenoid will increase by?

If the length of a solenoid is doubled and the current passing through it is increased 9 times, the magnetic field inside the solenoid will increase by?

اگر سولینائیڈ کی لمبائی کو دوگنا کر دیا جائے اور اس میں سے گزرنے والے کرنٹ کو 9 گنا بڑھا دیا جائے تو سولینائڈ کے اندر مقناطیسی میدان کتنا بڑھے گا؟
Explanation

If the length of a solenoid is doubled, and the current passing through it is increased 9 times, the magnetic field inside the solenoid will increase by 18 times.