98.33% of the sample is 70 years old and younger. To obtain the answer to question 1, you could have used the following commands:
tab age
The command above will display a frequency distribution table in the STATA Results window. Using this table, we find the value 70, which corresponds to 70 year old respondents. Looking at the "Cum." column, we see that the cumulative percentage is 98.33. This means that the observed category 70, and all categories preceding 70 in the table, make up 98.33% of the total observations in the data.