Statement 1
We know that Ram traveled the second half of the distance faster than 10 miles/hour. However, we don't know
[list =1]The total distance Ram traveled[/list]
[list =2]How fast Ram traveled the first half of the distance[/list]
So Ram's journey may have been 1 mile or 10,000 miles. He may have traveled the first half at 1 mile/hour or 100 miles/hour. This affects the duration of his journey a lot.
Statement 1 is insufficient
Statement 2
We know that the total distance Ram traveled is less than 5 miles. However, we don't know
[list =1]How fast Ram traveled[/list]
So Ram might have traveled at 1 mile/hour over the whole trip or 100 miles/hour. He might have traveled the first half at 40 miles/hour and the second half at 60 miles/hour. Again, big impact on the duration of his journey.
Statement 2 is insufficient
BOTH
Combining this information, we know the following:
So we know that Ram spent less that 15 minutes (2.5 miles at 10mph = 0.25 hours = 15 minutes) on the second half of the journey. However, we still have no idea how quickly he traveled the first half of the journey, meaning we have no idea the duration of time he spent traveling the first half of the journey. He could have traveled at the same speed during the first half as during the second half. Then, he would have finished the first half in 15 minutes, giving a total duration of 30 minutes. However, he could have traveled slower and finished in over 30 minutes. He could have traveled faster and finished in under 30 minutes. So we don't know if the duration of the journey was more than 30 minutes.
BOTH statements together are insufficient. The correct answer is E.