chemistry
posted by joe .
A reaction is 50% complete in 34.0 min.
1.) How long after its start will the reaction be 75% complete if it is first order?
2.)How long after its start will the reaction be 75% complete if it is zero order?
steps would be helpful

For 1 use ln(No/N) = kt
Use the 34 min and 50% complete to determine k, then use that k and the same equation to use the conditions in problem 1. 
So its Ln ( 50/100) = k (34 min)?

for the second part do i subtract 10075 = 25 = (the constant)(time)