Problem : log525 =?

2

Problem : ln(e2.7) = ?

2.7

Problem : eln(40) = ?

40

Problem : log63 + log612 = ?

log63 + log612 = log6(36) = 2

Problem : 3(log380-log34) = ?

3(log380-log34) = 3(log3(80/4)) = 3(log3(20)) = 20