Please help me . asap

What is the best way to answer questions with a x expression in the question. for example 3x + 10x=?

Events a and b are independent. the probability of a occurring is 2/5. the probability of b occurring is 1/4. what is p(a and b)?

Which is an accurate comparison of the two data sets? the commute to work is typically shorter and more consistent than the commute home. the commute to work is typically shorter but less consistent than the commute home. the commute to work is typically longer and less consistent than the commute home. the commute to work is typically longer but more consistent than the commute home.