If f(x)=2x and g(x)=1/x what is the domain of (f•g)(x)

In a two-digit number the units' digit is 7 more than the tens' digit. the number with digits reversed is three times as large as the sum of the original number and the two digits. find the number.

You are saving to buy a bicycle; so far you save 55.00. the bicycle costs 199.00. you earn 9.00 per hour at your job. which inequality represents the possible number of h hours you need to work to buy the bicycle?

Meee i honestly dont know what this question talking about