Tenses and Sentence function

Hi,
I have been working through an exercise, the majority of it went well, but I just need someone to help me to clarify some of the answers below.

The assignment first covers the 'Tense' of the question, followed by the function.

Thank you for help. It is much appreciated.

The Problem
Tenses: -

• Present Simple
• Past Simple
• Present Continuous
• Past Continuous
• Present Perfect
• Past Perfect
• Present Perfect Continuous
• Past Perfect Continuous
• Future with “Going To”
• Future Simple
• Future Continuous
• Future Perfect
• Future Perfect Continuous

Functions: -
A. A completed action at a specified time in the past
B. An action that happened before a specified time in the past
C. A definite future event
D. A newspaper headline
E. A past habit
F. A statement of regret
G. A recently completed event that has significance in the present
H. A request
I. A scientific fact or general truth
J. A state or activity that began in the past and continues down to the present
K. A threat
L. A piece of advice
M. An ongoing event in the past that was interrupted
N. An order or command
O. Reported speech
P. A routine
Q. Two continuous actions happening at the same time
R. An action which is to be completed before a specified time in the future
S. A plan

• I work from 6.00am until 1.00pm every day. - Present simple (J) -
  (This looks to me like this is 'a state or activity that pegan in the past and continues down to the present, but I am not 100% sure. As this could also be considered a routine (P), as there is a set time that a person has to be at work.)
  
  

• Snow melts when the temperature rises. - Present simple (Q) -
  (It looks like this is two actions happening at the same time, but this could also be (I), as this is 'a scientific or general truth.'
  
  

• She has been married for one year. - Present perfect (J) -
  (I figured that this is 'a state or activity that began in the past and continues down to the present.' But I wasnt sure if this can be classified as that. My other thought was that this could be (A), as this could be a completed action that happen in the past time.)
  
  

• At 10.30 I was driving to London, as I had missed the train.- Present perfect (M) -
  (I thought that this could be an event which was interrupted by timekeeping, therefore, required the drive down to London. I guess that this could also be (S), a plan, as the person would have to come-up with something due to this unfortunate event.)
  
  
• They’ll definitely have completed the job by Monday. - Future Perfect (R) -
  (This sounds like the job will be complete before or on Monday, which is why I chose (R). But this could also be (C), as this is a definite future event, as the job has to be completed by Monday.